In 2025, the Time Enforcement Commission, the agency set up to monitor time travel, has been in dispute with a rival agency, the Society for Historical Authenticity, that believes the technology should be used to change the mistakes of the past. When TEC agent Ryan Chang arrests their leader Brandon Miller for a failed attempt to assassinate Hitler, the latter escapes and sets out to remove all the time agents who opposed him from history.
This film provides examples of:
- Amazingly Embarrassing Parents: Chang materialises in a 1988 nightclub, and sees his young parents disco dancing.Ryan: "Mom? Dad? That is just so wrong."
- Badass Bystander: The second of Chan's ancestors who Miller tries to kill works as a hostess at a Chinese restaurant her boyfriend owns. Said boyfriend, the waitress, and the cook all fight Miller with martial arts moves (and some cleavers in the cook's case), driving him away and saving his target without any help from Chan.
- Butterfly of Doom: The villain, who was one of the former students of the protagonist's father (a physics professor and time travel theorist), has a heated argument at a lecture in 2002 about whether time travel implies an obligation to undo the tragedies of the past. His teacher warns him about the possibility that something worse may happen in their place.
- Deliberate Values Dissonance: Springfield, 1881:Jim: "We don't serve your kind in here."
Chang: "What kind's that?"
Jim: "What kind is that? Well, I could tell you, Chinaman, but I might just have to kill you. So, if I were you, I would just back out those doors... before you buy the business end of Ol' Smokey, here."
- Doppelmerger: An encounter between an individual and their past self will cause the two to involuntarily fuse into a horrific melding of flesh.
- Eyepatch After Time Skip: O'Rourke sports an eyepatch when Chang returns from trying to stop Miller.
- Future Me Scares Me: The villain scares his past self. So much that his younger self may change his future.
- Great Offscreen War: The first sign that Miller ignoring Hitler's Time Travel Exemption Act is having unpleasant consequences like Josh Chan warned are constant vague references to a catastrophic war where Doc's husband and Chan's parents died and O'Rourke lost an eye.
- He Who Fights Monsters: Brandon doesn't realize he's become like the monsters he wished to erase from history. Or does but doesn't care, presumably under the belief that it takes one to kill one.
- Hitler's Time Travel Exemption Act: In the opening the protagonist has to stop the well-intentioned but extremist villain from assassinating Hitler at a concert precisely because of the possibility of unforeseen consequences.
- Identical Grandson: Two of Chan's ancestors (1881 Soiled Dove Rose and her granddaughter, 1929 restaurant hostess Frances) are played by the same actress.
- Laughing Mad: The 1988 nightclub's patrons when the meat cleaver from 1929 follows Chang:"Dude, I am telling you - the air opened up and it flew right into the wall!"
- The Lost Lenore: The death of his wife Sasha makes Miller more brooding and ruthless. He imagines a stranger having her face in one scene and is awestruck to briefly encounter her again when he travels back in time to 2002.
- "Mister Sandman" Sequence: For each scene set in the past, instead of the date subtitles in the original film.
- Never the Selves Shall Meet: Coming into physical contact with your past self in this movie does not cause the person in question to melt out of existence, but results in them fusing into straight-up Body Horror.
- Officer O'Hara: Agent Ryan Chang is forced to defend himself against some belligerent ones in late 19th-century Atlantic City.
- Ret-Gone: The villain goes on a mission to erase all his enemy time agents from history so that he can interfere in history undisturbed.
- Sacrificial Lion: Jeffers has a lot of prominence for the first third of the film as an Action Girl and Chan's friend and partner. Then, once Miller gets the means to Ret-Gone his enemies, Jeffers is his first victim. She gets better in the final scene.
- Set Right What Once Went Wrong: Played with, as both the hero and the villain are trying to set right what once went wrong from their own perspectives. The villain is a Well-Intentioned Extremist who wants to be allowed to correct the mistakes of the past, only to be stopped by the time agents because of the possibility of disaster. When he proceeds to erase them from history, the hero goes back to undo his tinkering before he suffers the same fate.
- Time Is Dangerous: As opposed to the launch pad from the first film, here they use a different method of travel which can cause the time traveler to disintegrate upon departure, which is increasingly more probable if the same person goes through it repeatedly within a short period of time (from his/her point of view).
- Timey-Wimey Ball: The sequel plays with time travel much more than the first one. In the end, it is implied that all the preceding events of the movie never happened because the villain accidentally changed his own past.
- Well-Intentioned Extremist: The villain, Brandon Miller, believes that time travel should be used to right the wrongs of the past by actively interfering in established history. He is willing to go to the extent of erasing all his opponents from history and doesn't care about the possibility of unwanted and unforeseen outcomes.