Follow TV Tropes


Series / NUMB3RS

Go To

We all use math every day. To predict weather, to tell time, to handle money. Math is more than formulas and equations: it's logic, it's rationality, it's using your mind to solve the biggest mysteries we know.

A Police Procedural revolving around an Odd Couple of crime-solving brothers. Don Eppes (Rob Morrow) heads a team of FBI investigators called on to solve the exceptionally sensitive and baffling crimes that happen in Los Angeles about once a week. To solve these highly complex crimes, he invariably turns to his brother, Charlie (David Krumholtz), a college professor and mathematical prodigy, who applies pure mathematics to the task of solving crimes.

Ultimately, math conquers all...though on the way, Charlie usually faces a crisis of faith stemming from the fact that, while he's a mathematical genius, he is emotionally immature, with only a very slight understanding of human motivation. Balance is restored via the assistance of his father Alan (Judd Hirsch, a veteran of three other TV series produced by Paramount) and physicist colleague Larry (Peter MacNicol). Larry generally advises him to steer clear of messy human-interaction problems, while Alan nudges him toward a better understanding of human nature.


The show finished its sixth and final season in 2010.

The show's storylines were supposedly inspired by actual cases.

This series provides examples of:

  • Absentee Actor:
    • Alan (Hirsch) doesn't appear in the season two episode Dark Matter.
    • Larry doesn't appear in much of season three due to MacNicol's commitment to 24.
    • Similarly, Megan also doesn't appear much in season three due to Diane Farr's pregnancy.
    • Only Don (Rob Morrow) and Charlie (David Krumholtz) appear in every episode.
  • Absent-Minded Professor: Both Charlie and Dr Larry Fleinhardt are prone to this. Charlie gets better as the series progresses, but Larry is prone to being so deep in contemplation of either physics, math, or philosophy that he forgets what's going on around him.
    Larry: Let me ask one thing. When we met just now, was I coming out or going in to the library?
    Charlie: Coming out.
    Larry: [sighs] My memory is a memory. All right. [starts back inside]
    Charlie: [yells] Larry, you were coming out!
  • Advertisement:
  • Accidental Murder: The opening scene of "Rampage", involving a man busting into the FBI office and start shooting everything up, ends with a fusillade of bullets, and one man dead: a suspected pedophile the team was interrogating at that moment. It turns out that Colby's bullet was responsible, on account of the bullet going straight through the attacker's shoulder, through the office window, and into the pedophile's head.
  • Action Girl: Terry Lake, Megan Reeves, Liz Warner, and Nikki Betancourt.
  • Adult Fear:
    • Any episode that deals with kidnapping especially as the criminals responsible are shown to be violent and not above killing the people they take to prove a point or tie up loose ends.
    • In "Bettor or Worse": Not only are a mother and daughter kidnapped, but it turns out the husband/father was responsible.
  • All for Nothing:
    • Season 3 episode "Democracy" involves one of Charlie's mathematician friends being killed, along with several of her associates, on account of the research they were doing, which could possibly be used to rig voting machines and elections. The prime suspect escapes prosecution due to one of his subordinates taking the fall, but Charlie takes his friend's research and publishes it in the paper, allowing the state legislature to know exactly what to look for in the machine's software and stymie any attempts to rig the elections.
    • Season 5 episode "Sneakerhead" involves the theft of $250,000-value sneakers. The victim ends up basically stealing them back, but when he goes to look for them in the end, it turned out that his son found them, thought they were a birthday present for him, and wore them out in the rain.
  • A.I. Is a Crapshoot: Briefly holds Amita hostage and turned out to be fake.
  • All Guys Want Cheerleaders: In the episodes "Dark Matter" and "The Running Man", Megan asks Colby what he was into during high school and college, and both times his answer is "Cheerleaders".
  • All Your Base Are Belong to Us:
    • Season 2 episode "Rampage" starts with a man charging into the FBI office and start shooting, almost catching Charlie in the crossfire.
    • In "Chinese Box", a former contractor holds David hostage inside an elevator in the FBI building.
  • Alternate Reality Game: Chain Factor, an addictive little Flash game which went rather deeper, including clues scattered throughout one episode, online sites, and the Los Angeles subways to unlock various power-ups.
  • Amazingly Embarrassing Parents: Alan Eppes can be this at times.
  • Ambiguously Jewish: The Eppes family were this for the first couple of seasons; the third season episode "Provenance" established them as non-observant Jews.
  • Amicable Exes: Don and Liz, after their relationship ends in season four.
  • Analogy Backfire: The Director of Homeland Security refuses to shut down his anti-terror drills when one of them gets attacked with a gas that put six people in the hospital.
    Director's assistant: Stop the drills now, it's like turning the Titanic.
    Megan: The Titanic hit an iceberg!
  • Anti-Hero: Ian Edgerton.
  • Author Filibuster: In "Money for Nothing", the plot stops dead in its tracks for five minutes so Charlie and a guest star can lecture Colby on the wonders of microcredit.
  • As Himself: Penn Jillette of Penn & Teller guests stars in the season five episode "Magic Show'.
  • Asshole Victim: Frequently. Occasionally paired with Sympathetic Murderer, but in other cases, the killer is just as bad as the victim.
    • Special mention goes to the series finale, which is just a pileup of these. Don loses his gun during an arrest, and it becomes a symbol for people who feel the police aren't protecting them. The three people actually killed are two drug dealers and a chronic drunk driver; there are also near-misses on a man who's been abusing his ex-girlfriend and a bully who's been terrorizing his neighbors.
  • Awesomeness by Analysis: Subverted. The super-brain Charlie Eppes tries, among other things, golf and sniping, and learns that knowing the math simply isn't enough. It requires some kind of instinct or gut feeling to get it right.
  • Back-to-Back Badasses: Don Eppes and Billy Cooper in Man Hunt.
  • Badass Bookworm: As of Season 5, Charlie can SO kick ass. One FBI training course and BAM!, he has a gun.
    • This is subverted. Yes, he can target shoot, but still isn't much good in a real fight.
    Sinclair: It's a lot different when they're shooting back, okay?
    • He also can't do much else. Before his success on the range, he failed miserably at vehicle pursuit, hand-to-hand, and dynamic entry.
  • Bait-and-Switch: In the middle of "Backscatter", a bank manager is accosted by some goons and stuffed into the back of a truck. He starts pleading that he hasn't told the FBI anything... only to look up to see the FBI agents he'd met earlier, who had accosted him to get him out of sight of the Russian mob, who they figured out are blackmailing him.
  • Bait-and-Switch Tyrant: Mildred Finch in Season 3, as the new division chair of Charlie's department. She initially starts off getting on Charlie, Larry and Amita's cases for a number of issues, but provides insightful expertise in several FBI cases and soon warms up to the group (even dating Alan for a spell).
  • Bald, Black Leader Guy: David Sinclair. Although not technically a leader, he is Don's second-in-command.
    • Don gives him the lead on a few projects, and he also becomes the head of the unit when Don is injured in "The Fifth Man".
  • Batman Gambit: Charlie proved to be pretty good at this in episodes such as "Prime Suspect" and "Primacy". His strategies for trapping criminals include working out their plan so he could predict their course of action, and setting everything up so that to the criminal it seems everything is going according to plan, up until the point the trap is sprung.
    • One example can be found in "Backscatter". With the bank manager being held hostage by a Russian mob hacker who's plundering his systems, he's able to swipe the hacker's phone and send the number to the FBI. Charlie then calls the hacker to threaten him, leading the hacker to call his boss for confirmation, thus leading the FBI right to the boss.
  • Bavarian Fire Drill: The fifth season's "Jack of All Trades" features a criminal who is basically a master of this. He can fake his way into any job simply by turning up the charm. When he's finally captured for the first time, he escapes from jail by pretending to be an attorney.
  • Beeping Computers: Most user interfaces seem to make an unusual amount of beeping, whining, and chirps as the user scrolls and clicks.
  • Berserk Button: Threatening or hurting Charlie is a surefire way to piss off Don.
  • Beta Couple: Larry and Megan.
  • Big Brother Instinct: Don towards Charlie. Amusingly, big brother Don also works for "Big Brother". But then in this case, Big Brother is also your friend.
    • As a frequent consultant for the NSA (National Security Agency), Charlie works for "Big Brother" as well.
    • Don also acts like a big brother to the entire team. And the other members of the team often treat Charlie like a little brother.
  • Big Disaster Plot: Thirty-Six Hours, which has the team dealing with a train accident.
  • Black Best Friend: David Sinclair to Don as his Number Two. Even moreso to Colby. They get so close that Nikki starts giving them crap about it.
  • Bland-Name Product: CalSci to Caltech. Though the latter is actually an inspiration.
  • Brains and Brawn: The two Epps brothers, with Charlie being the brains and Don being the brawn.
  • Brief Accent Imitation: In "Bettor or Worse", David pretends to be a package delivery man with a Caribbean accent to get a suspect's father to open the door to his house so the FBI can pull him out without him getting hurt before they raid his house for the suspect.
  • Buffy Speak: Sometimes used when describing Charlie's equations.
    Megan: Well, there's always Charlie's inequality... bounding... thing.
    Colby: There is always Charlie's "inequality bounding thing".
  • Call-Back: Several.
    • At the end of "Growin' Up", Nikki and Colby remind David about one more piece of paperwork that needs catching up: his physical training. They bring out one of the counterfeit primers from the "Sneakerhead" episode the season before.
    • "End Game" and "Arrow of Time" get special mentions for this. Both episodes were call-backs to earlier episodes, but unlike the standard two-parter, it wasn't consecutive. "End Game" is a half a season after the setup episode "Thirteen", and "Arrow of Time" is a full two seasons after "Spree/Two Daughters".
    • "Disturbed" uses an equation to track down a serial killer, the very same one used in the first episode "Pilot". David even remembers it and is the one to explain the math.
  • Calling the Old Man Out:
    • Megan does this at one point to a millionaire who acts incredibly cold and distant towards his own daughter, though it is more of a Freudian Excuse due to problems with her own father.
    • Don's not above doing this to powerful people if he thinks they deserve it.
  • Catchphrase: "Everything is numbers." Or, perhaps, "everything is numb3rs."
  • The Cameo: The season 2 episode "Dark Matter" features well-known Broadway actress Marin Mazzie as the mother of a suspect. She appears in one scene and has only two lines.
  • Celebrity Paradox: At the end of Season 3 Episode 7, Alan tries to cheer up Don, who has just revealed to his dad and brother that his girlfriend had dumped him a week prior, by finding something fun to watch on TV. What we hear from the TV is the theme from the 70's sitcom Taxi. Alan is played by Judd Hirsch, who was the main character on Taxi.
  • Character Death: Dwayne Carter and Mason Lancer in the season four episode "Trust Metric".
  • Character Development: A very good amount of it, and not always in predictable directions (lookin' at you, Fleinhardt). Probably more so than most other Police Procedural shows.
  • CIA Evil, FBI Good: Mostly absent, even the NSA group that shows up is mostly on the level. However, there is the storyline involving CIA mind control experiments.
  • Content Warnings: Season 5 Episode 8 "Thirty-Six Hours" deals with a train derailment. It was written and filmed before the tragic Metrolink crash in Chatsworth, CA but was shown after. David Krumholtz gives a content warning that establishes the episode was written and filmed before the tragedy and gives a warning so those who might find the story disturbing can make an informed decision.
  • Cloud Cuckoolander: Dr Larry Fleinhardt
  • Cloning Blues: The "kidnapped" girl in the Hydra episode.
  • Cold Sniper: Agent Edgerton.
  • Continuity Nod: One episode mentioned a gang called the 18th Street Mexicali, a rival of the gang one of the suspects belonged to. Two episodes later, the gang is mentioned again as a gang that a record-label executive—and the father of the kid kidnapped in the episode—is connected to.
  • Contrived Coincidence:
    • In "Vector", the FBI is called in by the CDC to help investigate a viral outbreak (given the possibility that it may have been an act of bioterrorism). Don wants to bring Charlie, but the CDC insists on using their own mathematical consultant who has the proper clearance. Naturally, the CDC consultant turns out to be Charlie.
    • In Season 5 Episode 7, a family friend of the Eppes asks Don to look into his surfer son's death, ruled an accident. Don looks over the Park Ranger investigation into said accident at his desk and thinks the investigation was pretty thorough as Colby walks by and recognizes Don's Surfer friend. It is Colby, an Idaho farmboy, who realizes the death was murder because he just happens to be a hardcore surfing fan and notices a detail the park rangers missed.
    • The case in "One Hour" is this to some extent. The team gets a case while Don's at a therapy session with his phone off, and it just happens to be one with an incredibly short deadline, so much so that the case is fully resolved and wrapped up by the time Don shows up, when many FBI cases require days if not weeks of investigation.
  • Cop and Scientist: Cop and mathematician, but otherwise fits the trope.
  • Couch Gag: Each episode opens with a grid-patterned screen, each quadrant of which displays the number of something—suspects, dollars, crimes per day, people, whatever—relevant to its plot.
  • Covert Distress Code: In one episode, a rookie agent on once went undercover to catch a group of people kidnapping ATM users and was given the distress code "Mexico" to use if the operation starts to go south. It does, but she's too stubborn to use the word, believing that she can salvage the operation on her own. Don berates her for this later and assigns her to answering telephones.
    • "Mexico" is actually David and Colby's long-time covert distress code; each of them uses it once successfully (Colby in "Chinese Box", David in "Ultimatum") when the other is in a hostage situation, to warn each other that a hard entry is imminent.
  • Crime After Crime: The perpetrator of "Calculated Risk". Frustrated that his father isn't giving him respect at the family business, he embezzled around $300 million from the company, authored a scam to cover his tracks that possibly brought the whole company down, and then murdered the CFO when she started digging too deeply.
  • Criminal Mind Games: The episode "The Janus List" has a character who, in essence, does this for its own sake. He knows he's dying and wants to hand off his life's work, the eponymous list, to Charlie, but only if Charlie is worthy of it. So he hides the information behind a series of complicated codes and puzzles, which are in essence a test; if Charlie is able to get through all of the layers to access the list, then he's passed the test and proven himself worthy. He does, although one of the pieces ends up being figured out by Don.
    • Lots of episodes do this. Usually the clues require advanced mathematics to unravel, since the show's Aesop is that "Math is useful and mathematicians are like superheroes—with math."
  • Dark and Troubled Past: The brothers are mostly spared this (aside from their Missing Mom) but other characters are not so lucky.
    • Megan Reeves literally disappointed her father by being born female (she was his last chance to have a son), and she spent years trying to get his attention, first by positive means and then by acting out, until she finally ran away at 16.
    • David Sinclair grew up in a gang-ridden neighborhood, losing one of his best friends to gun violence when he was in high school. He also says at one point that his father died when he was about 14.
    • Colby Granger lost his father in a single-car wreck when he was 15; the cause of the wreck was never determined, but Colby always suspected it might have been a suicide, as his father had recently lost his job and was devastated. And that's not even getting into his time in the military, where he saw way more than his share of trauma.
    • Liz Warner's early life is never discussed, but she does say at one point that she had been pregnant in college and miscarried, and that her friends were so insensitive to her about it that she never spoke to them again.
    • Nikki's past is also not really explored, but we do know that early in her career, she was dumped into undercover work unprepared and one of the targets tried to rape her. The way she plays it off as no big deal also suggests she might have more (ultimately unexplored) trauma in her past.
  • Deadpan Snarker:
    • Colby can be this at times.
    • Megan Reeves is also this.
    • Nikki does this as well, with David being the usual target.
  • Decoy Damsel: One shows up in "Tabu". At first she appears to be kidnapped by an environmental gang as leverage against her businessman father, but then she starts shooting up the FBI with the gang and it's revealed that she co-opted the gang as part of a giant tantrum against her father.
  • Defensive Feint Trap: Used in the episode Assassin and discussed with a chess analogy.
  • Deliberate Injury Gambit: The climax of the pilot episode has Don holding the perp at gunpoint, except that he has David at knifepoint as a hostage. When the perp is suddenly distracted, David pulls the knife away to give Don a clear shot, even if it means gashing his wrist in the process.
  • Disproportionate Retribution: The kindly rec center owner who set off more than a half-dozen "chain reaction" gang shootings after a stray bullet killed his son, resulting in the deaths of hundreds of people, including innocent bystanders and children. Unsurprisingly, he's Driven to Suicide.
  • The Dog Was the Mastermind:
    • In "Structural Corruption", the mastermind behind the defective building cover-up turns out to be Cole's secretary.
    • In "Sacrifice", the killer is Scott, the victim's assistant.
  • Double Reverse Quadruple Agent: In "The Janus List", Ashby is said to have been this.
    Colby: By the time MI-6 cut him loose, nobody knew which side he was playing for.
    • Colby edges into this too in "Trust Metric". There comes a point when Don, Megan, and David can't even agree with each other about who Colby is and what he's up to. They do figure it out eventually.
  • Early Installment Weirdness: In the pilot, the viewer's first introduction to Alan is him playing with a pet bird in a cage. The bird disappears by the second episode, with a fish tank ultimately appearing in its place.
  • E = MC Hammer: Averted. The network actually hired professors to teach Krumholtz the real math he needed to know.
  • Empty Cop Threat: Not every episode, but on occasion. In the episode "Toxic", a private security contractor was found going through the files of a journalist the FBI was visiting. After confirming his credentials, and after the journalist declined to press charges, Sinclair let the contractor off with a warning that if they ever caught him near their investigation again, he would charge him with obstruction of justice personally. When the contractor was caught there again, Sinclair didn't charge him—he did something more drastic.
    • Actually, it was Edgerton who did something more drastic, and it was probably justified given that the guy was about to shoot another man in cold blood.
    • Another episode uses the trope: A man hires private security to find his stolen loot. The FBI is also on the case as people were kidnapped during the theft. The private security guys barge in as the FBI is about to arrest the kidnappers, which allows them to escape. Don immediately has both men arrested as an accessory to the kidnappers, and warns their employer that if he sees any more of his employees following FBI agents around, he'll have him arrested under the same charges.
  • Entitled Bastard: One shows up in "Money For Nothing", as an investor who put a large amount of money towards medical relief supplies for Zambia, but when the shipment gets stolen, demands that his money be returned to him and even hires private security to track it down themselves.
  • Epic Fail: In the episode featuring the hacker on the run from various criminal groups, the Israeli hacker/arms-dealer gets cornered by an FBI agent while said Israeli hacker's muscle is elsewhere. The hacker's eyes dart over to the glass window and the viewer just knows he is going to try and make a break for it—but does not expect for the break to fail so spectacularly, as the hacker's body (appropriate for his specialty, and thus not made like a linebacker's) bounces off the window not once, not twice, but three times. He is caught, obviously, no doubt wondering why the breakaway glass didn't break away, like in the movies.
  • Et Tu, Brute?:
    • The team is visibly crushed when Colby is revealed to be a double agent for the Chinese, especially David. After things are cleared up, their relationship is rocky for several episodes before they finally get it together again.
    • Lieutenant Walker is furious when he learns that one of his fellow cops, a narcotics officer, was so intent on clearing the streets of drug dealers that he secretly collaborated with a gang member to clear rival stash houses, organised the informant to go down in a raid when he wanted to come forward, and even killed the officer that pulled the trigger when he got suspicious. Especially since he helped raise his murdered colleague's son afterward.
  • Eureka Moment: Charlie, all the time, mostly highlighted by scenes of mathematical analogies and formulas flickering past his eyes.
    • Amita does it while Charlie is otherwise occupied in "Checkmate", leaving a bemused Larry to wonder, "What is it about this office?"
    • Larry gets one too, in "All's Fair". It being Larry, it's a somewhat literal interpretation.
    • Don gets one in "The Janus List"; Charlie, who's not used to being on that side of it, is both amazed and somewhat taken aback.
      Charlie: Is that the face I make when I...?
  • Everybody Hates Mathematics: Played with, inverted, and subverted. Several characters, including lead Charlie Eppes, love math, and those who don't love math are dependent on those who do.
    • Hell, by the sixth season, some of the FBI actually explain the math, with Charlie grinning like a proud teacher.
  • Evil Counterpart: Quite a few episodes had the criminal being a genius Charlie could relate to.
  • Expy: Bill Nye. Played by Bill Nye.
    • Another example would be the villain of the Season 5 finale: a very intelligent cult leader who has a bit of a god complex and whose followers are only women. He's played by James Callis. There are few differences.
  • Explosive Stupidity:
    • The arsonist villain of "Scorched" tries to hold off the FBI with a container of white phosphorus. He bangs his head while trying to escape through a pipe and drops the container, incinerating him alive.
    • David and Colby corner a shotgun-wielding suspect in a garage that was recently used to make bombs, and the suspect firing his weapon causes the residue to explode and kill him. However, he clearly did recognize the danger posed by explosive residue in the air (the earlier parts of the episode had him getting his associates to smoke outside), so his mistake is more likely the result of panic, or it might even have been an intentional Suicide Attack.
  • External Combustion: Takes out potential witnesses in "Democracy" and "Pay to Play"; another almost gets killed in "Blowback," but the bomb goes off too soon.
  • Extremely Protective Child: Joel, the grandson of Holocaust survivor Erika Hellman, is incredibly protective of his grandmother, especially when it comes to her quest to win back the Pissaro painting that had belonged to her father before the Nazis stole it when they sent them to the death camps.
  • Failed a Spot Check: The villain of "Primacy". For all that he knows about Amita (whom he's targeting for winning a MacGuffin in an online game), including her name, address, workplace, etc., he somehow fails to notice that she often works closely with the FBI, and is thus taken off guard when his kidnapping attempt turns into an FBI trap for him.
  • Fakin Macguffin: Where the MacGuffin in question is a math equation. A mathematician had his daughter kidnapped so that his ground-breaking solution to the Riemann hypotheis can be used as a codebreaking tool. When Charlie finds out that his solution will not work, Don comes up with the idea of giving them a fake solution that will open an electronic door that the FBI would set up for them that allows them to track down their location, allowing the FBI to raid it, arrest the criminals, and save his daughter.
  • Fake Defector: Colby Granger turns out to have been a triple agent for several years. This causes a fair bit of drama and angst, since the rest of the cast find out about the "defector" part well before they find out about the "fake".
  • Fatal Family Photo: "Burn Rate" starts with a Fatal Family Montage; the initial Victim of the Week is seen enjoying a moment with his wife, son and daughter before heading to work. When he receives a letter bomb, the debris is seen raining on a family photo.
  • FBI Agent: Half the main cast is one. For the whole series, Special Agents Don Eppes and David Sinclair. For some seasons, Special Agents Terri Lake (Season 1), Colby Granger (Seasons 2-6) Megan Reeves (Seasons 2-4), Liz Warner (3-6) and Nikki Betancourt (5-6), plus frequent guest star Ian Edgerton.
  • Feed the Mole: The strategy used in the episode "Assassin".
  • First-Person Perspective: In later seasons the show used gun barrel perspective as the FBI agents performed operations intercut with more regular footage.
  • Five-Man Band:
  • Foreshadowing: Before Colby was revealed to be a Chinese spy:
    Just the two?
    Just the two. Only one we need alive is the reporter.
    • The previous episode, "Money For Nothing", also contains a conversation between Don and Colby about loyalty that's rather prophetic.
      Don: How well does anyone know who they're working with?
      Colby: The way I see it, you got a team, you got to trust 'em. That's just the way it works.
    • Larry remarks in "Sniper Zero" that if he ever got a chance to go to outer space he wouldn't hesitate at the opportunity. In season three, guess what he gets to do.
  • Friendly Enemy: Charlie Eppes and Marshall Penfield in the fifth season story "Frienemies".
  • The Gambling Addict: The episode "Double Down" reveals that Larry was once one, and although he got out of the habit, one of his fellows wasn't as lucky. Said fellow got some of his students into the card-counting realm of cheating casinos, and the situation ended with two of them dead and another one in jail. Larry is disgusted at what his old friend got his students into.
  • Game of Nerds:
    • Dr. Fleinhardt is a Dodgers fan.
    • There is also another nerdy character that plays Fantasy Baseball, Oswald Kittner, who's played by Jay Baruchel, who is a real-life friend of David Krumholtz, according to the DVD commentary on that episode.
    • Charlie is also somewhat implied to be a fan, as he calls it "the most statistically driven sport in the world" with a note of pride in "Sacrifice" note  and chuckles in agreement when Alan jokes that you don't need statistics to predict that The Dodgers aren't going to win the pennant that year.
  • Gentleman and a Scholar: Charlie and Larry in different ways. Amita, too.
  • Good Parents: Alan.
    • Margaret Eppes, too, judging by the way the entire surviving Eppes clan talks about her.
  • Good with Numbers: Charlie, of course.
  • Gracefully Demoted: In Don's backstory, he was the Special Agent in Charge of the FBI Field Office in Albuquerque but took a demotion when his mother got sick from cancer so he could transfer to the LA office to be nearby her and his other family.
  • Hair-Trigger Explosive: Subverted. The perpetrator of "Protest" tries to hold off the FBI with a stick full of blasting gel, known to be much more powerful than dynamite, but is tackled when Colby correctly declares that blasting gel might be more powerful, but it's also more stable, and won't go off from simply being dropped.
  • Heroic BSoD:
    • Charlie goes through a lot of these.
      • He goes through one in the very second episode when Don is placed in a life-threatening situation because he followed Charlie's advice:
        Charlie: [frantically] The fact that you survived is an anomaly and is unlikely to be the result of another such encounter.
      • He tries to work himself into a safe space by trying to solve the famously difficult P vs. NP problem. Don isn't happy about this since Charlie buried himself in the exact same problem after their mother got cancer, and it takes a while to coax him out of it.
      • He gets another one in "Rampage" due to the trauma from the shooting attack at the FBI (especially since he almost got caught in the crossfire), to the point where he refuses to go back there for a few days afterward.
      • He goes into worse ones in Season Five when Don is stabbed and nearly dies and three episodes later when Amita is kidnapped because a terrorist wants to use her for her computer skills.
    • The mathematician in "Prime Suspect" has one when his solution to Riemann's hypothesis, which his daughter was kidnapped for, turns out to have a critical flaw that renders it incorrect, and thus worthless to trade for his daughter's life. Fortunately, Don and Charlie comes up with the idea of giving them that fake solution and rigging it to open a fake FBI electronic door, thus revealing their hideout's location and allowing the FBI to raid it and successfully save his daughter.
    • Also in "Rampage", Colby takes it pretty hard when it turns out that his bullet was what killed the suspected pedophile during the shooting attack, even after all of the evidence shows that it was an accidental death because the bullet Colby shot through the attacker's shoulder to stop his rampage accidentally landed in the suspect's head so it wouldn't threaten his job at the FBI. Mainly because it reminded him of a similar incident during his Army days when his troop accidentally attacked a British troop mistaking them for Afghan enemies, which resulted in two British soldiers dying.
  • Heterosexual Life-Partners: David and Colby. At least until they decided to play their Ho Yay for laughs.
  • He Who Fights Monsters:
    • In "Dark Matter", the mastermind of the school shooting does have a sympathetic motive (she was raped at a party and wants to get revenge on the people involved), but the fact that their way of doing so also put hundreds of school kids who had nothing to do with what happened in harm's way pretty well cancels out any sympathy they might have had.
    • This is discussed heavily in "Killer Chat", since it's about a Knight Templar Serial Killer murdering child molesters.
  • Hidden Depths: Colby speaks Spanish, which helped them on a case that had missing Spanish girls.
  • Hollywood Nerd: All over the place, but Charlie is the most prominent.
  • Hot Teacher/Hot for Teacher: Amita is young, brilliant, and attractive, and typically wears flattering casual clothes while teaching. She's also dating and eventually marries her thesis professor Charlie, though they don't start dating until after she finishes her thesis, when he's no longer in a position of authority over her.
  • How We Got Here: "Blowback" begins with a montage of scenes from late in the episode, then skips back to the beginning of the case.
  • Idiot Ball: The FBI has an unlimited supply of those.
    • YMMV on this. Charlie is more of a face for the real life technicians and consultants that would really be used by the FBI. The techniques tend to be rather standard, Charlie is just Mr. Exposition about how the techniques work. And having him as a university professor is fancier than an official FBI analyst.
    • One wonders, how often did the FBI catch criminals before Charlie started helping them? An episode illustrates the FBI's helplessness brilliantly. A man is accused of shooting an FBI negotiator during a face-off with the FBI. He flees after saying he's innocent He really is, and the FBI has been hunting him for months. It's repeatedly mentioned that every cop in the county wants to catch the guy, because he's a suspected cop killer. The bullet that killed the officer flew out of his body, and yet, despite the zeal with which the FBI wants to catch the guy and have him condemned, no one tried to find the bullet that killed their officer, if only to reinforce their case against the guy once they catch him. The bullet is lodged in a tree, with a prominent bullet hole, so it's not like finding it is hard (in fact, once the protagonists decide to look for it, they find it in a few hours) The bullet does prove the guy's innocence, but since no cop knew that, it still wouldn't explain why they never tried to look for it.
      • The idiot ball on that one is played with. The thing is, the house was surrounded by police who were intent on watching the house. They knew there was an armed man inside and they were prepared for that man to fire on them. No one expects a drug company to sell him a tainted vaccine, then when the government catches on to the tainted beef to then hire a sniper to frame the man for murdering a hostage negotiator. Every one at the site, faulty witnesses as they may be, would testify to the fact that they were watching the house at the time of the shot and that the armed man was inside. When they are cops at the scene of the crime negotiating with a man who has threatened to shoot them and then someone gets shot, it's kind of justified to think the same man is shooting. Plus, they had the bullet that was inside the negotiator. They just neglected to make sure that the trajectories were right. Probably because they were storming the building and taking him to cover. Later, they do actually just haul the Idiot Ball around. See the next reference for this episode.
      • In the same episode, it's mentioned how surprising it is to the FBI's expert manhunter that the fugitive never tried to leave his home county, despite it being in his best interest to do so and avoid the intense police presence searching for him. The cops repeatedly found the campsite where he stayed, but just after he's just vacated it. Yet it takes Charlie and his math to reveal the obvious: The man's sticking around his home county because he goes to visit his wife once in a while. Said wife still resides in their home, where the shooting took place. That's right. The FBI, and their expert tracker, NEVER considered that a fugitive who remains near his home might be visiting his family on a regular basis.
    • In another episode, they ask an interviewee if she knows anything about pot. After denying it, she mentions that she doesn't know anything about pot farms. They treat it like a Suspiciously Specific Denial. Of course, they do turn out to be right.
    • Garden variety Idiot Ball that seems to occur just about every episode: agents, usually David & Colby, approach a guy to ask him a few questions, identify themselves from about fifty feet away, guy then looks around nervously and bolts in the opposite direction, leading to a foot chase. These are experienced FBI agents? You'd think they'd have learned by now.
    • A more proper Idiot Ball is with Millie's reaction to the consulting that her professors do. Given the government contracts that could bring in, that seems like something that they should encourage.
  • I'd Tell You, but Then I'd Have to Kill You: Played straight by Charlie in "Assassin" (S02, E05).
  • If Jesus, Then Aliens: This trope seems to crop up with distressing regularity. Every few episodes, Charlie is challenged to move beyond the empirical world to a matter of faith, only the matter of faith in question is something completely outside the normal debate of science vs. religion, and yet Larry's right there urging Charlie to consider that it might possibly be true. After all, even scientists don't pretend that they can know everything, right?
    • More like Larry's just weird that way. If anything, his entire character exists to pointedly avert the Straw Atheist scientist stereotype while other scientists (like Charlie) take a more traditional view.
    • Actually, it's more that Larry is a physicist whose focus is on Quantum Mechanics in subatomic theory where the observation of a particle changes its nature and the reality of a subject of inquiry can be both existent and non-existent concurrently depending on the parameters of study. Hence, he spends most of his time theorizing on things that change when he observes them. Spending a career on that requires an existential trust in both stable and unstable influences that are constantly interchangeable. i.e., he has to have faith in stuff that isn't there because half the time when he finds it is there, it actually isn't.
      • Nonsense, particle physics and quantum theory aren't faith based, nor are they more predisposed to that sort of thinking. That's like saying statisticians are prone to the same thinking because they study systems with probabilistic behaviour. Or, people studying GR are moral relativists because "everything is relative" to them. Or students of nonlinear dynamics have messy houses and don't keep appointments because chaos theory and their subject being about not being able to control outcomes. Etc. Larry seems like a new age 60's hippie that got into physics - kind of reminds me of some (not all) is the early drug chemists that made psychedelics.
      • It may also be the other way around, that Larry was already prone to that kind of existential thinking, and that's what drew him to quantum mechanics, in the same way that, while not everyone who studies relativity is a moral relativist, a moral relativist might be drawn to relativity in the scientific sense.
  • I Have Your Wife: It happens at least once per season, but fortunately the FBI usually intervenes before anybody can get seriously hurt.
    • "Prime Suspect" involves four criminals kidnapping a mathematician's young daughter because they believed he solved the Riemann hypothesis, which can be used as a master key to crack several internet encryptions, and they're using her get the solution as ransom.
    • In "Rampage", the man who shot up the FBI office was threatened by a contract killer hired by an arms dealer to get him acquitted from his current trial to go through with it or else he'll kill his wife and daughter. Rather than kidnap them outright (which would have tipped off the FBI to the real motive behind the attack), the contract killer uses surveillance photos to show the guy how easy it would be to find them and hurt them. It's also played straighter when a critical witness in that arms dealer's case has his family kidnapped by said contract killer.
    • "Backscatter" has some bank employees captured (one of whom is pregnant) by the Russian mob to coerce their boss into letting them access his bank for their robbery.
    • "One Hour" involves the kidnapping of a record dealer's son.
  • I Just Shot Marvin in the Face: In one episode, a movie star's friends are being blackmailed, and the secret is this trope.
  • Illegal Gambling Den: In one episode, the team uncovered a gambling website where patrons can bet on a Russian Roulette-esque Deadly Game. The premise is that a revolver will be loaded with a single bullet and players take turns pulling the gun's trigger while it's pointed at them. The loser is the one who pulls the trigger while the bullet is in the position where the revolver can actually fire it.
  • Informed Flaw: It's mentioned a couple of times in early seasons that Charlie is a terrible speller, such as when he when he gives an eight-letter word for egotistical as "conceted". It doesn't have much effect on the plot, but it does give his family a means of deflating his ego when they switch games from chess to Scrabble.
  • Infraction Distraction: Used as gambits by some criminals.
    • "Rampage" involves a madman breaking into the FBI office and start shooting the place up, allowing an inside man to smuggle out some confidential data during the evacuation to assist in getting an arms dealer acquitted.
    • "Backscatter" involves Don and his family personally targeted by the Russian Mob, preventing them from looking too closely at the bank the mob is trying to plunder of its secure info.
  • Instant Marksman: Just Squeeze Trigger!: Both downplayed and somewhat justified in "Sniper Zero". Charlie's bullet ballistics number-crunching keeps failing to give him the whole picture of how the suspect sniper operates, so he resolves to learn what shooting a gun feels like. After struggling with a rifle at the shooting range for a while, Don gives him a few of the usual pointers: relax his hands, shoot in-between breaths, etc. Charlie's next shot, while not sharpshooter material, is a lot better, and his final prediction on the sniper's nest location is off by only a few feet.
    • Don also points out to Charlie that there's a difference between shooting paper targets and real people. He may primarily be referencing the emotional impact, but the same is true of aiming. (Charlie and David have a similar conversation four seasons later, in which David clearly is referring to marksmanship.)
  • Inspector Javert: One shows up in "Burn Rate", believing that a past suspect of a serial bombing case is up to his old tricks. He isn't, and even has to save her from a bomb himself.
  • Insufferable Genius: Charlie can on occasion be this. Just enough times to give him human faults.
  • Interdisciplinary Sleuth: Charlie solves crimes with mathematics!
  • Interrupted Intimacy: In "Man Hunt," the FBI tracks down one of the escaped felons to his girlfriend's house, and they raid it to make the arrest just as they're in the middle of having sex.
  • It's for a Book: Used by the villains of "Dirty Bomb". They contacted a researcher for a nuclear company for information about a particular radioactive isotope (how to handle it safely and stuff like that), claiming they were doing research for a movie script. Because the series takes place in Los Angeles, the researcher wasn't suspicious until she saw an internal Department Of Energy alert warning that three caskets of the isotope was stolen to make a dirty bomb. She subsequently contacted the FBI, which proves useful in finding the identities of the criminals.
  • It's Personal: Happens quite a bit.
    • 'The Janus List"/"Trust Metric" is one of the biggest examples for the team. Megan put it best:
    Megan: Why are we doing this? We're acting like this is any other case, and it isn't.
  • I Want Grandkids: Alan takes the proactive approach, giving solid relationship advice to Don and Charlie.
  • I Want You to Meet an Old Friend of Mine:
  • Jerk Jock: The Jocks who raped Karen in Dark Matter are this.
  • Jurisdiction Friction: Almost completely absent. Don's FBI crew has a tendency to work and play well with others. They especially have a good relationship with the local cops.
    • As shown in "Brutus" and "Finders Keepers", though, the CIA and NSA are another story.
  • Just Smile and Nod: The FBI gang do this when Charlie explains some very complicated math theories.
    Charlie: Right, no, we have to consider variegated terrain and a considerable time gap. Compensate for the time lag. Add overlapping search spirals to maximize the area covered...
    Edgerton: ...Anyone else following this?
    Granger: Just nod your head and wait for the punchline.
  • Just Like Robin Hood: One shows up in "Robin Hood", natch, who robs a bank known to have customers with seedy connections and gives the proceeds to charity.
  • Kick the Son of a Bitch: "Rampage" starts with the team working on a pedophile case with the suspect in interrogation. Said pedophile becomes a victim of collateral damage and the only fatality when someone else bursts into the office and starts shooting up the place.
  • Killed Off for Real:
    • Trust Metric: Mason Lancer and Dwayne Carter.
  • Knight Templar: Several.
    • The man who lost his son to gang violence, and starts setting off "shooting chains" to cause as many gang member casualties as possible.
    • The woman who had her husband molest their daughter, kills him in revenge, and starts tracking down other pedophiles to torture them, get their confessions, and then murder them to prevent other children from being molested.
    • The man who was a victim of a hit-and-run that went cold, who started assaulting every person he sees responsible for road danger.
  • Knight Templar Big Brother: Don... he has gotten better about it over the years, though.
  • Know When to Fold 'Em: In "Prime Suspect", four criminals kidnap a mathematician's five-year-old daughter because they believe that he solved the the Riemann hypotheis, which can be used as a codebreaking tool to hack through banks' digital encryption and they're using her to get the solution as ransom. When the FBI raids their hiding place and arrests two of them while killing the third in self-defense, the last kidnapper holds a handgun to the kid's head in an attempt to salvage the situation in his favor. Fortunately, Terri manages to subvert the Hostage Situation by pointing her rifle through a window at his head, giving her a way to kill him if he tries to harm the girl or escape. The kidnapper realizes he has no moves left, so he lets the girl go and surrenders.
  • Lady of War: Megan, Liz, and Nikki all fit this trope to varying degrees. Amita has her moments as well.
  • Layman's Terms: Once an episode Charlie or one of his colleagues references an obscure mathematical concept that can be used to help solve a case, then creates an analogy to make it understandable. The team has come to expect them and basically ignore the math and wait for the analogy. See Just Smile and Nod.
    • This predictable behavior is lampshaded in "Brutus" when the agent prompts him for the analogy: "Imagine..."
    • Occasionally inverted by Larry for laughs, who takes everyday situations and complicate it by adding cosmological terms.
  • Letters 2 Numbers: Or, if you prefer, L3tt3rs To Numb3rs. The show also did this in its opening sequence. The names of the actors would slide across the screen to the right as numbers, resolving then into the letters of the actors' names, except for a couple of them, which would remain briefly before then switching over to the letters.
  • Let Off by the Detective: The episode "Robin Hood" involves the robbery of a bank frequented by suspected antiquities smugglers and drug dealers, who are robbed and the proceeds from returning the spoils/retrieving the goods given to charities. When the team finally track down the bandit (who was the brother of a firefighter that died in the arson burning of a homeless services house, orchestrated by the bank manager who wanted to develop the land), they have already arrested the manager for conspiracy of the arson and the arsonist himself, so Don mentions the man's upcoming trip to Venezuela and recommends he stay there for a good long while.
  • Loads and Loads of Characters: While the core duo Don and Charlie, appear in every episode, and characters like Alan, Amita, David, and Colby are almost always present, there's a revolving cast of other characters who are so known to the audience that their appearance is nothing special, but who still don't make it into every episode.
  • Magical Defibrillator: Averted altogether in the season five episode "The Fifth Man". While in the hospital,Don's heart goes into fibrillation and the defibrillator is used to restore a normal rhythm. You can see the monitor displaying an erratic heartbeat. When he flatlines, they use a syringe filled with a drug to attempt to revive him, not the paddles.
  • Mama Bear: A dark example in "Killer Chat"; Elaine Tillman found out that her husband molested their daughter (she knew he was a pedophile, but he had promised her he wouldn’t do anything to their children), so she murdered him in revenge. Then she started luring other child molesters to vacant houses under the disguise of a teenaged girl online, torturing them to get their recorded confessions, and then murdering them so no other innocent kid would go through what her daughter went through ever again.
  • Manly Tears: Charlie breaks down in Don's arms when he thinks Amita may have been killed.
  • Maybe Magic, Maybe Mundane: In Hot Shot it's not entirely clear if Alan and Charlie are dreaming or seeing visions of Margaret (JoBeth Williams) but it is treated like they are dreaming.
  • Meaningful Name: Amita Ramanujan. Srinivasa Ramanujan was a very famous mathematician.
  • Measuring the Marigolds: Subverted by Charlie in that he appreciates the beauty of the world, he just sees math as playing a part in that beauty.
  • Meet the In-Laws: In Pay for Play Charlie goes to meet Amita's parents and he is nervous about it. Things do get awkward but Amita's parents do eventually accept him when they meet him.
  • Misplaced Retribution: The villain of "Judgement Call" has this as their motivation. A detective got killed and his killer caught, but though the jury advocated for the death penalty, the judge overruled them. For years after, the cop killer made numerous appeals for retrials, agonizing the detective's widow with every moment that looked like he'd go free. In the end, through her husband's old contacts, she found a hitman to go after the judge's wife, to make him think about "the next criminal he goes easy on".
  • Minor Crime Reveals Major Plot:
    • "Calculated Risk" has the FBI investigating the murder of the CFO of a company that just went under, but Charlie's analysis reveals that the murderer killed her because she might've found out that he was embezzling money from the company and then authored a scam to cover it up, which may have also brought the company down behind him.
    • "Black Swan": An apparent innocent bystander at the scene of a drug raid flees from the cops, and the FBI discovers that he's involved in a domestic terrorist bombing plot.
    • An Invoked Trope in "Robin Hood"; a high-tech bank robbery turns out to be just one piece in an intricate scheme to expose the misdeeds of the bank's president.
    • "Assassin": While busting a passport forger, the FBI discovers evidence of a plot to murder the last member of an influential South American political family.
    • "Waste Not": A sinkhole suddenly forms underneath an elementary school playground, killing a teacher and injuring several children. During the investigation into why it happened, it's revealed that a construction company has been dumping toxic waste barrels underneath the playgrounds they've built at several low-income schools.
  • Monty Hall Problem: A topic of one of Charlie's lectures in an episode.
  • Motive Misidentification:
    • The Season 2 episode "Backscatter" has Don and his family directly targeted by the Russian Mob after arresting a couple of phishers connected to them near a bank. Don thinks that It's Personal, but in actual fact, they're targeting him to distract him from investigating the bank, which the mob is planning to rob.
    • In "Sacrifice", it initially appears that a researcher was killed to steal his research. In reality, his killer found his research horrifying, and killed him to stop him from completing it.
    • In "Rampage", a man breaks into the FBI office and starts shooting everything up, but only a suspected pedophile the team was interrogating right before the attack is killed. The FBI initially assumes that the attacker was getting revenge on the pedophile for molesting somebody he knew, especially when they find out the attacker has a daughter in the age range that the pedophile liked to prey on. Then it turns out that Colby was responsible for the death because the bullet he shot through the attacker's shoulder to stop his rampage accidentally went through the interrogation room window and landed in the pedophile's head. Furthermore, the attack itself was a distraction to allow an inside man to smuggle out some confidential data about the witnesses to an arms dealer's current trail during the emergency evacuation so a contract killer can kill and/or threaten the witnesses into silence to get the arms dealer acquitted; the attacker was also an unwilling accomplice, as the contract killer threatened to kill his family if he didn't do the attack.
    • "Pandora's Box" involves an intentional plane crash, killing five people. The FBI at first thinks it's due to the prototype scramjet being transported on it, when the real purpose was to hide a virus on the flight data recorder, get the FAA to hook it up to their mainframe, and insert code that would allow the perpetrator to conceal planes from their radar - perfect for drug smuggling.
    • "Blackout" starts with multiple power substations being vandalized all over the city. Theories are thrown around from causing a cascading failure of the grid to union dissent, before it's revealed that the aim was to drain the fuel supply for a prison's backup generators, so that they'd call in an emergency delivery of fuel, allowing the bad guys to use the tanker as a Trojan Horse and infiltrate the prison so they can assassinate one of the inmates.
  • Mr. Fanservice: Charlie and Colby. The former appeals to fans of cuter Pretty Boys and the latter to fans of Hunks. The producers are clearly aware of Charlie's attractiveness, exploit it and often makes him emote and Colby has his own fair share of angst, particularly when it comes to the army. Colby also has a thing for getting into the water, and let's not forget the Ho Yay.
  • "Killer Chat"; the case is about a Knight Templar serial killer who targets child molesters and finds victims by posing as a teenage girl online, leads them to an empty house, then tortures them to get their recorded confessions. They then murder the molesters.
  • Nazi Gold: In "Provenance", a Pissaro painting lent to a small art museum is stolen. An old Jewish woman and Holocaust survivor named Erika Hellman, who was born in Berlin, claims that it had belonged to her family before they were all sent to the Nazi death camps, and she has been in a court case with the current owner of the painting (who inherited from his Army veteran father after he bought it when World War Two was over) trying to win ownership of it when the episode starts. Both her grandson, Joel, and the current owner become suspects, the former because he's fiercely protective of his grandmother, and the latter because he had a massive insurance payout on the painting. However, in the end, it's revealed the museum curator stole it because he found out that the painting is a fake, much to everybody else’s surprise. The original is found to be sitting in a police vault in Budapest, because Erika's father had commissioned an art forger to recreate the painting and gave him the original for safekeeping so the Nazis would be stealing a fake instead of a priceless painting, and when the Hungarian police arrested the forger in 1946 they had assumed that the painting was one of the fakes they were confiscating as evidence. The episode ends with the Hungarian police sending the real painting to the FBI and Don giving it to Erika and Joel, allowing them to have one piece of their pre-World War II family heritage back.
  • Never Suicide:
    • One case is set off by an apparent suicide of an engineering student, which Charlie is convinced was actually a murder because he discovered a big, expensive secret about a skyscraper's faulty construction. While the student did discover the secret flaw, his death was a legitimate suicide because he was already suffering from depression and thought nobody would listen to him any other way.
      • This episode was Very Loosely Based on a True Story. In 1978, an engineering student discovered a very serious flaw in the Citigroup Centre building in New York, that could cause it to collapse in winds over 70 mph. In the real world, he told the architect, who very quickly realized that he was right, and the architect, builder, and owners of the building undertook immediate action to correct the problem. They also informed the city of the problem, and made evacuation plans for the area surrounding the building (though they still kept it a secret from the public) and started watching the weather very carefully until the problem was fixed.
    • Played straight in "Guns and Roses" and "Democracy".
  • Nice Jewish Boy: Charlie, though non-observant.
  • Non-Action Guy: Charlie.
  • Obstructive Bureaucrat: Subverted by Floyd Thompson of Department 44.
  • On Three: Delivered by David to Colby, via a Multitasked Conversation, when a gunman has them dead to rights.
    David: Give us one good reason why you're doing this. Okay? Give us two reasons. (Beat) Three!
    (David and Colby spin around and start firing.)
  • Ominously Open Door: Trope Namer. It happens enough to get a a lampshade hung.
  • Omnidisciplinary Mathematician: While far less egregious than other cases, Charlie is an expert at far more fields of math than is realistic, even for a genius like him.
    • Amita too, occasionally.
  • Only Bad Guys Call Their Lawyers: Played With. While some of the bad guys do have lawyers (in "Waste Not", the lawyer was actually involved with the crimes), innocent people do occasionally bring a lawyer along when they're being interviewed by the agents. For example, in "Harvest", a patient was discovered with an illegal kidney that he got from a Back-Alley Doctor. The patient's actual doctor immediately contacted his hospital's legal department since he knew law enforcement was going to notice the black-market organ (at the time he didn't know a girl was accidentally killed in order to get the kidney but he knew that the incident was still going to be investigated and that he would be questioned as part of it) and they paired him up with a lawyer for when Megan went to interview him and collect his patient's medical information. His having sought legal counsel is never treated as a sign of guilt.
    • Another aversion shows up in "Dark Matter". Two shooters attack their high school and when the FBI figures out there was a third person involved, all the members of the school’s video game club become suspects because the two shooters were avid members of the club and were the closest to them out of anybody at the school. Their parents respond by hiring lawyers to help defend their innocence. While the FBI agents react with slight annoyance at this because it impedes their investigation, it's never treated as a cause for increased suspicion. At the end it turns out that the third shooter wasn't involved with the video game club at all; she was a school newspaper club friend of the other two shooters who was raped at a party and masterminded the shooting to take revenge on the people involved.
  • Open Mouth, Insert Foot: When Don first goes to the department shrink, he is originally dismissive and criticizes the shrink for working out of a textbook with no idea what the FBI is like. He changes his tune when the shrink reveals his own past in undercover narcotics, and doesn't appreciate Don not respecting his past job and expecting him to respect his.
  • Oral Fixation: Don is usually seen chewing gum when he is keyed up during climatic scenes, mostly waiting for the suspect.
  • Organ Theft: In "Harvest", four Indian girls come to the United States, each intending to sell a kidney willingly on the black market to get money for their poverty-stricken families. However, the first girl accidentally dies from a surgical error, and the Back-Alley Doctor running the organ ring decides to kill the two girls he has left (one of the surviving girls ran and hid inside another part of the hotel basement when the first surgery got botched and was taken into FBI protective custody as a crucial witness when Don and David found her) in order to harvest all their organs for the money and to get rid of any potential witnesses. One of the girls ends up dead, but fortunately, the FBI interrupts just before the procedure on the second girl begins, and she is rescued unharmed.
  • Papa Wolf: Do not try to hurt any of Don's team. And DO NOT try to hurt Charlie.
  • Paranormal Episode: The series had an episode with a psychic helping the FBI, much to Charlie's annoyance, who got rather jealous of the psychic's performance.
  • Parental Abandonment: Not quite, but Amita's parents are always too busy to see her.
  • Parental Marriage Veto: Subverted. Amita and Charlie are both very worried that Amita's parents won't approve of Charlie because he's not Indian, but when they finally actually meet Charlie, they are immediately won over.
  • Pay Evil unto Evil: The Theme Serial Killer of "Thirteen" is sniped while in FBI custody by a soldier who was the boyfriend of his very first victim.
  • Perp Sweating: Happens a lot.
  • The Philosopher: Larry, who stayed at a Buddhist monastery for quite a long time and often nudges Charlie in matters of philosophy. Somewhat of a Justified Trope—he studies quantum physics.
  • Phlebotinum Analogy: Charlie often uses these so he can explain his mathematical analyses to those around him.
    Megan: I'm so hoping you have one of those cute little analogies for this.
    Charlie: As a matter of fact, I do.
  • Playing the Victim Card: The main villain of "The Running Man", while faking it the whole time. He claims that his mediocre origins kept him from getting into prestigious colleges in favor of the applicants with hard-luck stories, so he re-enters universities under different names and personas and always with hard-luck origins to sympathize his way in and to get the false celebrity of being a person who beat impossible odds for a better life, vanishing after a year and stealing expensive equipment to finance his schemes. David isn't particularly convinced when the suspect keeps bragging about his rough origins (since he knows from experience that having a rough childhood is something you want to put your distance from when you manage to escape for a better life) and isn't particularly sympathetic when they finally catch him.
  • Pregnant Hostage: "Backscatter".
  • The Professor: Larry and Charlie. Especially Charlie, who is incredibly smart and was once a Teen Genius.
  • The Profiler: Megan's specialty.
  • Public Secret Message: In "Counterfeit Reality", an artist is kidnapped by a gang of forgers to replicate the art on dollar bills for them, but secretly puts imperfections in the counterfeit bills that, when viewed a certain way, provides the FBI with her location, just like how she encodes messages to her husband in her art.
  • Pyrrhic Villainy: In the episode "Democracy", the FBI ends up facing a hedge fund investor who rigged an election and then arranged for all but one of the witnesses to be murdered and has someone else take the fall so he walks free, but because Charlie published the math used in the case, election officials would know what to look for and stop any other rigged elections.
  • Quirky Curls: Charlie is a male example.
  • Rape Is a Special Kind of Evil: The darkest episodes of the series are ones that resolve around Serial Killers and rape. It tells you something when in the episode "Dark Matter" the perpetrator who orchestrated a school-shooting is portrayed somewhat sympathetically: all the students deliberately targeted, including her best friend, were complicit in a plot to have her raped after doing a school article on steroid abuse by the school teams. The sole surviving conspiracist is treated as a Jerkass about to get a taste of his own medicine.
  • Real Time: The third season episode "One Hour", in which, while Don talks with his therapist (who has made him turn off his cell phone), the rest of the team has just one hour to crack a case.
  • Reality Ensues: In the pilot episode, no less: Charlie uses his mathematical skills to determine the general area where a serial killer lives based on the locations of his murders, but the FBI fails to find a single viable suspect in the target area. When the FBI finally catches the guy, it turns out that he used to live in the target area, but had moved away prior to the beginning of the episode. No matter how good your math is, there will always be some variables that you can't account for.
  • Redemption Equals Death: Dwayne Carter, when he shoots Mason Lancer just before he injects Colby with a lethal chemical and gets shot himself shortly after, or at least as close as he ever gets to redemption.
  • Red Shirt: Averted. In one episode, a squad infiltrates a hidden marijuana farm, with several no-named agents. After having specifically stated that those kinds of farms are booby-trapped, it results in an anticlimax where several are disarmed, and nobody gets hurt.
  • Remember the New Guy?: Colby and Megan are introduced in Season 2 with little fanfare or even proper character introductions. They're simply dropped into the team like it's no big deal. Justified, as the FBI is a large bureaucratic organization and these sorts of personnel changes are probably so commonplace as to really not be that big a deal.
  • Remember When You Blew Up a Sun?: Colby Granger from Season 4-6 gets several comments referring to the fact that he was a triple agent.
  • Ripped from the Headlines
    • "Sniper Zero" (S01, E09) seemed to be all about the Beltway Sniper Attacks.
    • In "Calculated Risk" (S02, E04), it sounded like they were reading directly from Enron's wikipedia page.
  • Running Gag
    • Alan walking in on Charlie and Larry doing some experiments in their house, from building a model complex out of cereal boxes, measuring how ice melts with the house's thermostat, or messing with the shower.
    • A popular one in the later seasons is that whenever the FBI field agents go to a potential suspect, and the suspects run, the agents tend to treat it more as an annoyance than an actual worry that the suspect might get away.
    • There's also one that surfaces occasionally in Charlie's tendency to mistreat whatever random food happens to be lying around to demonstrate a math concept.
  • Russian Roulette: Used as a way to make money from very desperate gamblers and really sick viewers. The organizers even gave the players nicknames and everything; unfortunately for them, it was rigged.
  • Self-Fulfilling Prophecy: In one episode, a psychic predicts the killers' next move and goes there with his camera. The killers are there, along with their big truck. He doesn't get better, either.
  • Shipper on Deck: Nikki seems to be this with David and Colby. She's made several comments about the two of them in a relationship.
  • Shorter Means Smarter: Charlie.
  • Shout-Out:
  • Sibling Team: Don and Charlie.
  • Sibling Yin-Yang: Don is more "jock-like" and Charlie is more "geek-like".
  • Smart People Play Chess: It isn't enough that Charlie Eppes could multiply four-digit numbers in his head when he was three, graduated from high school and entered Princeton at 13, completed his bachelors degree in three years and is a multiple PhD. No, just so we'll know he's really smart, he regularly beats his father and his former academic adviser (both portrayed as above-average intelligence) at chess, too.
    • Justified. Chess is a proponent of game theory with a zero-sum outcome in which all information is available and possible moves are restricted based on previous moves. Hence it really comes down to a calculation of possible outcomes weighed against a target outcome. The reason why mathematicians tend to be good at chess is because chess is based in a very specific form of game theory. Why does Charlie always play and always win? Because he's Good with Numbers, chess is about as close as game theory gets to pure mathematics, and he's a mathematician. Although, considering that most of his math deals with statistical models and application it would probably be more appropriate for him to be playing black jack.
      • Which Dr Fleinhart did to the point of being banned from casinos, making him doubly smart!
    • It's been shown that the only way to have a reasonable chance at beating Charlie at chess is for two people to play against him at once while also having a distraction.
    • Mostly averted with Millie, who, after challenging Alan to a game, admits to Charlie that she's never actually learned how to play and has to try and learn the game in the day and a half before she's set to play him. She does beat him, but her approach to the game is less pure strategy and more people-reading skills. (She's very good at poker.)
  • Smurfette Principle: At least early on in the series. The cast is mostly male with one female FBI agent at a time (Terry first, then Megan takes her place) and Amita. This is then subverted in Season 3 when they add Liz, but Amita is still the only female character who lasted the whole series.
    • That's more a case of Real Life Writes the Plot, as the actresses who played Terry and Megan both left the show for personal reasons.
  • Sole Survivor: In "Provenance", Erika Hellman was the only member of her family in Berlin who survived the Holocaust.
    Erika: You have no idea what it's like to be the only survivor of your family and to have no idea why.
  • Spanner in the Works:
    • The killer acts as a villainous version of this for Charlie in the pilot episode: He develops an equation that is meant to identify the killer's home based on the locations of his previous offenses and it would have done exactly that if not for the fact that the killer happened to move out of the identified area a few weeks earlier.
    • In "Bettor or Worse", the plan for a jewelry store manager with massive gambling debts and a bookie in a lot of trouble to pay off their associates by arranging for the manager's family to be kidnapped and for the bookie's sister to rob the store is derailed by the lone security guard shooting the robber.
  • The Spock: Dr Fleinhart. Charlie doesn't qualify, as he emotes just fine.
  • Standard Cop Backstory: The show has a few.
    • Megan Reeves was wealthy, but her father resented her because she was born a girl, and it's hinted (but never confirmed) that there's more to the story. Whatever did happen, it was bad enough that she didn't speak to him for over a decade.
    • David Sinclair grew up in a poor neighborhood "dodging gangs just to get [his] high school diploma". His father died when he was in his early teens, and one of his best friends was killed in a random act of violence (for which another friend was unfairly blamed).
    • Colby Granger's father died in a single-car wreck when he was fifteen. There's no way to be sure, but Colby has always suspected it might have been a suicide. He also spent several years in the military.
    • Recurring character Ian Edgerton also has a military background; the rest of his backstory is a complete unknown.
    • Notably averted with Don. Charlie's being a prodigy caused a few small issues, but he was always loved and cared for. There's a reason that he's still so close with his family. He does have a few failed relationships, but that's implied to be mostly by choice.
  • Stealth Hi/Bye: The specialty of mysterious government Agent Floyd (minus the "Bye" part), to the annoyance of Amita: "Stop materializing out of thin air!"
    • Cold Sniper Edgerton also has a habit of doing this, but, then again, he is a sniper. He made a surprise appearance at the end of Season 6, then asked why he wasn't invited to Charlie and Amita's wedding that was planned in one day.
  • Stealth Pun: Possibly the name Eppes constitutes one. Amita: "Charlie, wonderful news! You are now father of an...Eppesilon!" (Don't Explain the Joke mode: Famous mathematician Paul Erdős was known for calling children "Epsilons". It's derived from the Greek letter epsilon being standard use for the arbitrarily small quantity in the definition for the continuity of a function).
  • The Stoic: Don.
  • The Storyteller: Charlie Eppes teaches math with stories. He would be great to have as one's professor.
    • Larry indicates that he gets amazing class evaluations.
  • The Strategist: Charlie would probably qualify with his ability to mathematically predict the moves of evildoers.
  • Straw Vulcan: Usually averted.
  • Suspiciously Similar Substitute: Twice, and both times it has been the female FBI team member.
    • Not sure about Terri, but Diane Farr (who played Megan) was pregnant with twins at the time she left.
    • Kind of an interesting example, because while Megan shares characteristics with both the character she replaced (Terri) and the character who replaces her (Nikki), Terri and Nikki don't have much in common at all, it's just that Megan has very strong attributes that correspond with both. With Terri and Megan the trope comes into play as they're both The Profiler; with Megan and Nikki it's more about the Action Girl aspect.
  • Sympathetic Murderer: While it doesn't excuse their crimes, a lot of the killers do have sympathetic motives.
    • The one who caused domino-effect killings (he shoots at Gang A, who retaliates against Gang B, who retaliates back, people get caught in the crossfire...repeat until about 150 people are dead) to avenge his young son who was murdered by gangsters. By the time the crew catches up with him, he is very clearly insane.
    • The Knight Templar murderer who targets child molesters in "Killer Chat" turns out to be the wife of a pedophile who had sexually abused the couple's daughter. Despite the brutality of the crimes, it's hard not to sympathize with the killer once the motive is revealed.
    • The killer in "Sacrifice" becomes a lot more sympathetic when we learn his motive: the victim was developing a computer program that would have allocated educational resources based on a mathematical assessment of "potential" (as Don puts it, the government would use it to justifying taking money away from poor communities and making sure only the wealthy got opportunities), and his assistant Scott, who came from a poor neighborhood, knew that such a program would have denied him the opportunities that allowed him to escape for a better life, and that other people like him would be denied any opportunity for a better life if the program were ever implemented. Once he's arrested and explains his motives to Charlie, Scott compares what his boss was doing to the Nazis using the Theory of Eugenics to justify murdering the poor and those that they had deemed "undesirable", as both programs would take somebody's chance of life away due to factors beyond anybody's control. At the end of the episode, Charlie comes to agree with Scott that potential can't be measured mathematically, even though he doesn't condone the murder, and he destroys the victim's work so nobody else can take advantage of it.
    • One shows up in "Velocity". He was a street racer until he caused a fatal accident, whereupon he swore off it for good. But when some of his old racer acquaintances (who often drove past him to mess with him) caused a crash at one of his old hangouts and killed a new friend, he ended up beating the one responsible to death. That's the sympathetic part; the part where he kicked a 17-year-old who he thought was responsible for the crash in the head, less so.
    • The plot of the series finale involves two near-misses on this: a battered woman whose boyfriend keeps violating his restraining order, and a teenage boy whose neighbor has been bullying his family. However, the woman is unable to bring herself to do it, and the other attempt is interrupted by the FBI.
  • Teacher/Student Romance: Charlie and Amita. He's only her thesis advisor! Really!
    • Less weird in that since Charlie was a child prodigy, they're about the same age. Also, Charlie doesn't begin dating her until after she finishes her thesis, when he's no longer in a position of authority over her.
  • Team Dad: Don.
    • Alan, too. And not just in the sense of actually being Charlie and Don's father—he will at times give everybody useful advice or be a sounding board for problems.
  • Tempting Fate: When David and Colby corner a gun-wielding suspect in a garage that was recently used to make bombs:
    David: Sir, you're in a bomb lab! Now you know better than-
    Colby: ...apparently not.
  • Theme Serial Killer: A serial killer whose victims had the same names as the 12 apostles and killed them in the way each apostle died.
    • Not only that but the locations of their deaths were consistent with a map of the last significant events of Jesus's life.
  • Therapy Is for the Weak: After the Crystal Hoyle incident, Don is encouraged to go to therapy, and is initially resistant to the idea before he finally gives in.
  • This Looks Like a Job for Aquaman: Alan sometimes offers his insight on a few of Don's cases, usually relating to his old profession as a city planner.
  • Treacherous Advisor: Some episodes have certain advisors from other federal agencies (arson experts, anti-terrorism experts, etc.) advising the FBI with their case, but who turn out to have orchestrated the case themselves for whatever reason.
    • Subverted in "The O.G.". The guns used to orchestrate several shooting chains between gangs turned out to have all come from a gun buy-back program and all signed off by Lieutenant Gary Walker, who was advising the team up to this point, but this is because all the guns were dropped off at the same drop-off location, allowing the perpetrator to get his hands on them and use them.
  • Unit Confusion: Occurs in-universe in "Thirty-Six Hours". Charlie gives Colby a series of very precise directions to get into the wreck but forgets to specify unit of measurement; he means them in meters but Colby counts them out in yards, causing him to run into a dead end. Charlie figures it out fairly quickly, and it ends up being little more than a minor inconvenience.
  • Villain Has a Point: The victim in "Sacrifice" was killed because he was developing a computer program that would have allocated educational resources based on a mathematical assessment of "potential" (or as Don puts it, it’s a justification to take money away from poor communities and make sure only the wealthy got opportunities). His assistant, Scott, grew up in a poor crime-ridden neighborhood, and knew that such a program would have denied him the opportunities that allowed him to escape for a better life. He also knew that other people like him would be denied any opportunity for a better life if the program were ever implemented. Once he's arrested and explains his motives to Charlie, Scott compares what his boss was doing to the Nazis using the Theory of Eugenics to justify murdering the poor and those that they had deemed "undesirable", as both programs would take somebody's chance of life away due to factors beyond anybody's control. At the end of the episode, Charlie destroys the victim's work so nobody can take advantage of it even though he refuses to condone the murder.
  • Virtual Danger Denial: A Playful Hacker cheerfully pisses off a number of powerful agencies online, legal and illegal, and is in total denial that they could come after him in real life. At least until it gets one of his loved ones killed.
  • Walking the Earth: Larry is always doing this or wanting to.
    • Except when he went into space.
    • Then when he went into the desert.
  • The Watson: AKA the FBI.
  • Wedding Finale: The sixth (and series) finale had Charlie and Amita's wedding.
  • Well-Intentioned Extremist:
    • The scientist who intentionally infected people with Spanish Flu to prove that the pharmaceutical companies chose the wrong (less virulent) strain to use in the development of vaccines and treatments, because he was convinced that a real epidemic was only a matter of time and so getting it right was literally a matter of life and death.
    • The Homeland Security agent who saw vulnerabilities in counter-terrorism operations that had to be patched, and tried drawing attention to them by using a deadly gas in one of them (watered down to prevent casualties). When that didn't work, he planted a (fake) bomb on his boss to make him feel the fear of soldiers saddled with ineffective strategies and protections.
    • The Knight Templar Serial Killer in "Killer Chat" who targets child molesters so no kid would ever be hurt by one again after her husband molested their daughter.
    • The man who started killing gang members in such a way as to maximize retaliations, with the intent of getting as many gang members as possible killed off, after his son was killed in a gang war.
    • The narcotics cop who was feeding a gang member the locations of rival gangs' stash houses so he could raid them, figuring that fewer drug dealers was better for the community. He crosses the Moral Event Horizon when the gang member decides he's had enough and wants to come forward; he arranges for the gang member to go down in a raid, and then kills the cop who pulled the trigger when he starts to piece together that something wasn't right.
    • The Neighborhood Watch types who got ahold of Don's gun used it to kill a pair of drug dealers who sold to schoolchildren and a serial drunk driver who ran down two people, and to intimidate a vicious neighbor who turned out to be an escaped murderer.
  • Wham Line: From the Season 3 finale, "The Janus List". The entire episode has been about getting a list of double agents, not because they were seeking the list itself, but because its author is setting off bombs in a roundabout way, to make Charlie and Don prove they were worthy to receive the list. They figure out the clues, stop the bombs, and listen to the list...
    Janus List: Colby Granger, FBI, also working for the Chinese.
    • In the following episode, "Trust Metric", Big Bad Lancer gets one when he has Colby on the freighter:
      Lancer: That's a question I need answered, Agent Granger.
      Colby: Oh, it's not "Agent" anymore.
      Lancer: Mike Kirkland says differently.
    • A more personal example in "One Hour", when Don's therapist finally goads him into revealing the extent of his trust issues. It's as much of a Wham to Don himself as anyone, since even he hadn't been consciously aware of how bad his problem was.
      Don: Look, I'm their boss! I don't have to trust them; it's their job to trust me!
  • Will They or Won't They?: Charlie and Amita.
    • They Do: They got married.
    • And Don and Robin. In the final episode, they get engaged.
  • Working with the Ex: Between Terri, Liz, Robin, and even one-off characters like a counterfeit specialist from the Secret Service, Don runs into a lot of his Old Flames throughout the job.
  • Would Hurt a Child: The FBI deals with child kidnappers, pedophiles and violent offenders throughout many episodes, but one that takes the cake is "Waste Not", where a company responsible for paving school playgrounds also buried barrels of toxic waste underneath them, which eventually leaked and caused a sinkhole that trapped several kids and caused chemical rashes.
  • Writer on Board: The eco sub-arc, the season finale about treatment of minorities from "risky" areas of the world.
  • Writers Cannot Do Math: Zigzagged like crazy.


How well does it match the trope?

Example of:


Media sources: