- Every time Don starts bickering with a lawyer. Until he starts getting mad, that is...
- S2 E8: Though they are talking about Megan's recent trauma, Larry manages to invoke this.
Larry: This is not even taking into account the double-X chromosome situation.
Larry: Yeah, you know, women have two X chromosomes, men have an X and a so-called Y. But I think if you examine it closely, you'll find, as I have, that the 'Y' is really just an 'X' with a piece missing.
Charlie: Implying what?
Larry: Well, since I'm missing that very piece, I may not be qualified to answer, but I think it has something to do with, you know, they're just more sensitive.
Charlie: Or that they can bear children?
Larry: Eh, psh, that too, I guess.
- Sometimes Charlie's need for data can provide a few laughs.
Charlie: And can I also see all the arson records you have in the L.A. county you have access to for, like, the past year?
Arson Inspector: That's several thousand fires.
Larry: (to Charlie) Eh, that's a pretty limited sample.
Charlie: You know what...make it the past two years.
- "What flavor of crazy Kool-Aid do they make you drink in the physics department?"
- Really, Larry is just a fountain of these.
Amita: Oh! By the way, Larry called from his string theory conference. He was confused about something.
Charlie: What, his double-special relativity theory?
Amita: No, whether he was in St. Louis or Cleveland.
Charlie: He's so geographically challenged. Where is his conference?
- This gem, made even better by the WTF face Charlie pulls when he hears it.
Larry: Oh, I rarely dream. I mean, every once in awhile I have this recurring dream in which my Aunt Louise is attempting to consume my flesh, but as a general rule, no.
- In S2 E23, Colby and David are visiting an Asian strip club. They...don't exactly blend in.
Colby: We're the only white people in here.
(Beat, David looks at Colby)
David: Yes, we are.
- Alan and Larry having to deal with the annual tradition of students dropping pumpkins frozen with liquid nitrogen from the University's rooftops.
- Followed by Charlie's reaction when Alan and Larry decide "when you can't beat 'em, join 'em":
Amita: What was that all about?
Charlie: The two great adult influences on my life are heading off to blow up pumpkins.
- In the episode 'Arrow of Time', several prisoners broke out using a rope made out of dental floss. Liz showed Larry, Charlie, and Amita the rope and this exchange took place:
David: (referring to a rope made of dental floss) It's 30 feet long...
Amita: Floss is sold in containers of 20 to 150 yards... (gets questioning glances) I'm an informed shopper.
Charlie: Just eyeballing the density of this rope, I'm thinking it's gotta be... 18, maybe 19 thousand feet.
Larry: 3 and a half miles of dental floss, even assuming an average container size of 50 yards...
Amita: Mm, 127 rolls of floss.
Liz: You guys find new and special ways to freak me out all the time.
- The end of the fourth season episode Graphic, featured this exchange between comic book artist Ross Moore and Alan Eppes:
Alan: I — I have a little trouble picturing you as a hippie.
Ross Moore: (surprised) Whaaat??
Alan: ... Right!
Colby: Aw man, who's going to tackle this guy?
David *glances at Colby*: Whoever gets there last!
*Both speed up.*
- The chase finally ends when the man tries to carjack two women... and end up getting his naked ass kicked by said two women.
- 'Black Swan' has a few good quotes when the team are breaking into a house full of bomb making equipment:
- Megan has just crashed into the suspects car to distract them.
Megan: Oh my God, this is why you aren't supposed to text and drive!
- Colby is about to climb up the trellis to get into a upper floor window.
Colby: Yeah. Colby, go down the elevator shaft. Colby, jump in the bay. Hey, Colby, climb the Sixth Street Bridge.
David I went out on the bridge with you, okay?
- A good quote about the running gag:
David: Why do they always run?
Colby: 'Cause we wear suits, man. You always figure you can outrun a guy in a suit.
- Alan being a dad raises a smile every now and again.
Alan: I hear Robin's back in town.
Don: Yeah, I'm really happy she's back.
Alan: Did you tell her that?
Don: Not yet, not in words, no.
Alan: You know, it's guys like you that make Beyonce sing that "Single Ladies" song.
Alan: Great! Now I have two jaded, world weary sons!
Don: And this one's got a shrink to prove it
- After the house has been broken into and both sons are off to a crime scene:
Alan:Two sons that solve crimes and neither one cares.
- Then he gets his own back later during Charlie's leature:
Charlie: I can't believe it. Right in the middle of my lecture!
Alan: Charlie, I'm as embarrassed as you are
Charlie: You were snoring!
- Charlie's examples are always good:
- The one set in the Arctic and he's wearing an heavy coat.
- The one in 'Jacked' at a card table where Charlie is wearing a card dealer's outfit with Don and the bad guy sitting at the table wearing tuxedos, sunglasses and smoking big cigars.
- And occasionally Charlie changes the analogy:
Charlie: You know I, I've been running expressions assuming a dog chasing a cat. But its actually a dog chasing a cat, chasing a mouse!
Ian: I thought it was an airplane?!
Charlie: Oh well, cats and dogs work better now.
- An episode in Season 5, where the whole episode was rather bizarre (they were looking for a specific pair of shoes, for Christ's sake! Well, the shoes were worth like a quarter of a million dollars, but anyway...), but all of the wtf-ness of the episode was made up for entirely when at the end of the episode, when they've finally pinned the shoes. The dude who stole them, also the original victim, goes into his closet, takes out a box... and doesn't find them there. They then hear footsteps outside... and find out that the thief's son was wearing them, in the rain. Apparently he thought they were a birthday present. The thief says, "New shoes... $250,000...". One of the agents then replies, "A smile on your kid's face: Priceless".
- David and Nikki attacking the guy built like a sumo wrestler and Liz beating him with a fire hose.
- The episode "Frenemies" has Charlie reluctantly working a case with his arch rival Marshall Penfield. Naturally the two of them can't stop bickering, prompting a bored Larry to make the following threat:
Larry: Boys, don't make me pull the Math Car over...
- From the same episode, David and Colby making fun of Charlie and Marshall for accidentally making a field trip to a crime-in-progress:
(in deep, movie-trailer voice) In a world
where mathematicians go mano a mano with a killer—
(in a slightly raspier, creepier voice) This time, it's personal.
- The B-plot in the episode "Old Soldiers" involves David asking Amita for help buying a suit for an upcoming date, but she has trouble meeting his very...particular tastes. At the end ofthe episode she finds the perfect suit for David — an old one of Alan's from the 70s that she finds while she and Charlie are helping Alan sort through some old things in the garage.
- Agent Edgerton and Don are bickering in front of a suspect about to go into a conversation with some very scary people while wearing a wire.
Don: Don't worry, you got the fifth-best shot in the world covering your [expletive deleted].
Edgerton: [holds up shaking hand] Fourth-best. [looks at his hand] You don't want to know how I moved up a spot.
- Megan's struggle to identify a woman in Season 2 "Better or Worse"
Megan: The coroner's report on our Jane Doe? No traceable dental work. She's never even had a cavity.
Don: Yeah? So we have a jewel thief who flosses, anything else we can trace? Contact lenses, breast implants...
Megan: The contact lenses are generic mail-order, so there's no serial number there. And her breasts—believe it or not—are real! In LA! I mean, that wasn't the nose she was born with, which doesn't help us, but at least it will help ME sleep at night.
- It's dark, but in Season 6 Ep 3, the FBI is investigating a gambling game of Russian Roulette. In order to study the patterns, Charlie and Larry recreate the games with a couple of students, some football helmets and a Nerf gun. When they report their results to the team...
Charlie: But we didn't kill any students, don't worry.
[David's "Well, duh" face says it all.]
- Season 6, Episode 9. John Buckley (the mastermind behind the bus hostage situation) is assisting the FBI:
Buckley: Your brother, he really doesn't like me.
Charlie: Well, it takes him a while to warm up to people.
Buckley: Is that what it is?
- "Where Credits Due" follows them as they attempt to locate a killer who is re-enacting scenes from a up-coming movie, which is itself about a series of perfect crimes being committed. After a whole episode where the team have almost no evidence due to the nature of the crimes, it's eventually revealed to be the writer who was robbed of the original credit for the script, he's arrested as he's working on a new one that Colby takes and reads in the office.
David: Script really that good?
Colby: Yeah, and you got to read it. You know what's it about?"
David: No, no idea.
Colby: A prison break.
(Beat) [David makes a face as a thought occurs to him, proceeds to take the script and walks off]
Colby: What're you doing?
David: Making a copy. First thing in the morning, I"m sending it to the director of the detention center!
- Best part was both Colby running after him so he have the remaining pages to read and the fact that it may not have necessary: The real killer boast that prison will give him all the time he wants to make more scripts, he's crimes making the movie and him famous.
- In "Pandora's Box," the Eppes household is broken into and Charlie tries all sorts of complicated math such as "Heterogeneous Poisson Process" to try to crack the case. In the end, the case is cracked when they track the GPS in Alan Eppes's stolen laptop.