The star of the show.
- Action Girl: She's introduced getting up at four in the morning and practically demolishing her apartment for exercise.
- Ambiguously Brown: Lt. Atkins finds himself at a loss when trying to categorize her (after having categorized Geils and Tanner). She then states that she has a black father and a white mother.
- Broken Bird: She has been incredibly distant and confrontational following the disappearance of her former partner and fiance.
- Defective Detective: She begins the series as a loner workaholic who's reeling from the disappearance of her former partner/fiance. By Season 2, she's unwillingly caught in a love triangle, forced to watch another woman raise her baby, and dealing with the mysterious reappearance of her fiance all while investigating what turns out to be a far-reaching conspiracy. And this is before the second season even hit its halfway point.
- Even the Girls Want Her: Gets hit on by at least three women. Detective Lukin and Officer Partridge both try to kiss her (repeatedly, in the latter's case), while Scholls asks her out on a date.
- I Work Alone: Angie, who constantly asserts that she doesn't need help or a partner. Not even when moving a sofa.
- Standard Cop Backstory: She dislikes having a partner and letting people get close because her former partner and fiancé mysteriously disappeared while on the job. Then Season 2 sets up a conspiracy where he might actually be alive.
- She also claims to have had 236 former partners... all of whom met with terrible fates after they got too close to her.
- Unresolved Sexual Tension: With Geils. It's dialed Up to Eleven at random moments.
- Walking Armory: She carries at least three guns and a compound bow (in her trousers at the small of her back) while on duty.
- Workaholic: To ridiculous heights. She's been prone to obsessive fits that have led Atkins to force her to take time off.
The idealistic partner Angie gets saddled with.
- Epic Fail: Geils goes all in during a high-stakes poker game. Turns out his hole cards are a three and the card with the instructions on it.
- Mundane Made Awesome: Geils a longtime admirer of ventriloquism; he even had their trading cards.
- Put on a Bus: Is absent for Season 4, though still mentioned a couple of times.
- Salt and Pepper: Whenever he's partnered with Tanner.
- Unnecessary Combat Roll: Geils turns this into an entire gymnastics routine in the pilot episode.
- Unresolved Sexual Tension: With Tribeca. It's dialed Up to Eleven at random moments.
- Walking Shirtless Scene: His shirt frequently comes off. Sometimes without his even being aware of it.
Lieutenant Pritikin "Chet" Atkins
The bombastic boss of the department.
- Blood Brothers: Atkins has one with Commissioner Bigfish, who took a bullet meant for Atkins back in The '70s.
- Da Chief
- Hair-Trigger Temper: He's so easily angered that it's as if he's never calm.
- No Indoor Voice: He's perpetually yelling no matter his mood or the situation.Atkins: GEILS! TRIBECA! GET IN HERE!!!
- Retirony: Regularly talks about his impending retirement and how he intends to go sailing on a boat he recently bought. A writer assisting on a case says that she sees his arc ending in death.
- Strong Family Resemblance: Atkins' identical cousins are running police departments all over the country. He also has a twin brother Adventurer Archaeologist. And one that's the principal of the school Angie decides to teach at.
The no-nonsense streetwise detective and Hoffman's partner.
- Bilingual Dialogue: He speaks to Hoffman in English while Hoffman speaks to him in untranslated barks and growls.
- The Bus Came Back: Is gone for the majority of Season 4, but appears in one episode undercover as a fashion designer's assistant to pursue an embezzlement case.
- Heroes Love Dogs: He's partnered with Hoffman, with whom he shares a mutually loving relationship.
- Hidden Depths: He is a clockmaker in his spare time.
- Salt and Pepper: Whenever he's partnered with Geils.
- Scary Black Man: Played with; Tanner is not afraid to yell and get in the face of a perp, but it's not his normal nature.
- Token Minority
The furry, four-legged Only Sane Dog of the place.
- Action Pet: Hoffman takes down suspects, drinks hard, and drives fast cars.
- Bilingual Dialogue: His barks and growls are unsubtitled but other characters have no trouble understanding him and they reply in English.
- Identical Grandson: In Season Four, he's replaced by his grandson Hoffman, who for all intents and purposes is the exact same character.
- One of the Boys: Sure, he's a dog, but Hoffman drinks, drives, fights, and curses just like the rest of them.
- Team Pet: Averted. No one ever acknowledges that he's a dog and interact with him as if he were a human detective.
- Unusually Uninteresting Sight: He's a dog who's treated like a full detective and drives a police cruiser (even ripping donuts in a parking lot) but no one treats this as if it were out of the ordinary.
Dr. Monica Scholls
The brainy and beautiful medical examiner.
- The Coroner: Her main role on the show.
- FaceHeel Turn: Gets into a relationship with Joe Perry in the fourth season, and supports his latest scheme. In the season finale, it turns out she was The Mole.
- Ms. Fanservice: Treated as such, although she disappoints a roomful of men by stepping out of a bubble bath fully clothed.
- Omnidisciplinary Scientist: Primarily a medical examiner but she's also seen dabbling in other forensic sciences. If a specialist is needed, however, she'll call in Dr. Edelweiss.
- The Stoic: She speaks in a deadpan monotone no matter the situation. It takes a major revelationnote for her to show any emotion.
A medical specialist that acts as Dr. Scholls' boss in the first season.
- New Job as the Plot Demands: After he quits the LAPD.
A psychologist that joins the team in Season 4.
- Token Minority: With DJ Tanner's absence in (most of) Season 4, she fills this role.
Angela Jay "Angie" Geils
The child of Tribeca and Geils. In Season 4, he's all grown up and a member of the team.
- Contrasting Sequel Main Character: Geils is absent for Season 4, so A.J. takes his position as the lead male cop.. But compared to Jay Geils, he's far more cynical, due to his rough upbringing.
- Hilariously Abusive Childhood: Suffered one during the Season 4 Time Skip. The boarding school Tribeca placed him in closed after just six months, he was adopted by accountants but ran away because the math made him anxious, and then he got PTSD from the circus he ended up in.
- Late-Arrival Spoiler: His existence spoils Tribeca and Geils hooking up in earlier seasons.
The mayor of the city. Becomes Vice President of America in Season 4.
- Corrupt Politician: Does some underhanded things to gain power; Eddie Pepper claims he is the head of a city-wide crime syndicate, and is responsible for crimes including money laundering, racketeering, voter fraud, racketeering fraud, and voter laundering..
- Karma Houdini Warranty: In the Season Four finale, he's finally arrested after trying to hold A.J. hostage.
- Overarching Villain: Is responsible for a lot of the problems in Tribeca's life, such as motivating Sgt. Pepper to form Mayhem Global and keeping Tribeca behind bars during the Season 4 Time Skip.
- Start My Own: In the Season Four finale, he frames Tribeca and A.J. for stealing the Louisiana Purchase, as part of a gambit to turn the territory into a new country he can be President of.
Sgt. Eddie Pepper
Angie's former partner and lover. The leader of Mayhem Global, and main antagonist of Season 2.
- Broken Pedestal: Eddie has this with the law, of all things. He became disillusioned once he learned that Mayor Joe Perry was getting away with all kinds of crimes.
- Chekhov M.I.A.: He's first mentioned in the episode "The Wedding Planner Did It", when Angie tells Geils that he ran through a dark tunnel on a case once and was never seen again. In the second season, Sgt. Pepper turns out to be well alive and part of a huge conspiracy.
- The Conspiracy: Eddie Pepper creates Mayhem Global, an organization that is dedicated to bringing down Mayor Perry. Things escalate over time, and they go from trying to get him out of office to just killing him.
- Hoist by His Own Petard: Eddie Pepper recruits Angie to his cause against Mayor Perry. Guess who betrays him in the end?
- Well-Intentioned Extremist: His efforts to ruin Mayor Perry's campaign become more violent and illegal, resulting in more support for the Mayor. This leads to him resorting to murder and manipulating Angie into taking the fall for him in order to further his goals. In the end, he not only fails at what he was trying to achieve, but his actions basically lead to Mayor Perry's victory. Not to mention that Diane Duran disappears, allowing Geils to take her place. Also, Angie betrays him after being reminded that she has a child and therefore something to fight for. In the end, he is left all alone.
An FBI Agent.
A former small-time crook that's become "The Hunter", an animal rights activist and serial killer that targets animal hunters.
- Arc Villain: Of Season Three.
- Detective Mole: His introductory episode has him go by the alias Zachary Fontaine, a detective meant to help Angie and Giles track down The Hunter.
- Friendly Scheming: Is actually a Vice cop, whose victims were all soon-to-be-executed criminals, and the entire serial killing case was meant to test Geils to see if he's worthy of becoming a Lieutenant.
- Hoist by His Own Petard: In the Season Three finale, he gets mauled by a Bengal Tiger he unleashed at a wedding. Or at least, he would have if the tiger wasn't fake.