History Series / NUMB3RS

* SitcomArchNemesis: Marshall Pennfield, who is Charlie's old rival from Princeton. Near the start of the season two episode: "Convergence", he performs a lecture in which he finds a flaw in the Eppes Convergence, the mathematical theorem that made Charlie famous. Charlie will readily admit that Pennfield is brilliant; he just doesn't like him because he's an [[InsufferableGenius insufferable asshole]]. In the end, Pennfield helps Charlie figure out the case of the week, and when Charlie does find a way around Pennfield's problem, he calls it the Pennfield variation.

* CultureJustifiesAnything: The villain of "Trouble in Chinatown" tries to make this argument for [[https://en.wikipedia.org/wiki/Chinese_ghost_marriage ghost brides]], but given he's trying to force the issue by murdering undocumented Chinese women workers to give dead Chinese bachelors wives in death, no-one buys his argument. The Chinese-American ICE agent with the team even pulls a ShutUpHannibal by shouting "Shame on you!" at him. Larry later shows up to further explain that the villains were perverting the custom (the original custom involves pairing up people who are ''already dead''), just to make sure the viewers don't leave with the impression that there's an actual Chinese cultural ritual that endorses murdering women in order to give dead men wives.

** "Traffic": A hit-and-run victim starts [[KnightTemplar killing people associated with other accidents]]. It's implied it's not completely his fault that things are so out of proportion, as he suffered a several frontal lobe injury in his accident and has diminished impulse control.

* DiplomaticImpunity: This is briefly suggested as something Chinese spy Dwayne Carter might try, but Sinclair points out that they have the consulate under surveillance; since Carter isn't a diplomat himself, he'd be fair game as long as they got him before he was inside. As it turns out, Carter plans to exploit international shipping laws instead.

** In "Scan Man", the titular IdiotSavant is initially considered to be a suspect until the FBI actually meet him, huddled under a table watching an indy race on a portable TV and humming along to the cars.

* CultureJustifiesAnything: The villain of "Trouble in Chinatown" tries to make this argument for [[https://en.wikipedia.org/wiki/Chinese_ghost_marriage ghost brides]], but given he's trying to force the issue by murdering undocumented Chinese women workers to give dead Chinese bachelors wives in death, no-one buys his argument. The Chinese-American ICE agent with the team even pulls a ShutUpHannibal by shouting "Shame on you!" at him.

** Any sort of science denial is this for Larry, and ''especially'' if the denier tries to use religion to justify said denial. He nearly loses his mind in one episode when he's confronted with a cult that eschews modern medicine in favor of faith healing.

** Any sort of science denial is this for Larry, as shown in one episode where he's confronted with a cult that eschews modern medicine in favor of faith healing.

* BerserkButton: Threatening or hurting Charlie is a surefire way to piss off [[TheStoic Don]].

* TheMissusAndTheEx: Don's history causes to happen a few times.

* NoodleIncident: The incident that got Charlie's learner's permit revoked. The only thing we know is that it has something to do with radar guns, which Charlie strenuously insists are unreliable.

* SelfFulfillingProphecy: In one episode, a psychic predicts the killers' next move and goes there with his camera. [[spoiler:The killers are there, along with their big truck. He doesn't get better, either]].

* NonActionGuy: Charlie.

* FlashMobCoverUp: In the episode "Animal Rights", the villain organized a flashmob ahead of time to distract the authorities at a key moment.

* ColdSniper: Agent Edgerton.