Meanwhile, a convoy of survivors led by Carlos Oliveria (Oded Fehr), Lloyd Jefferson "L.J." Wayne (Mike Epps), and Claire Redfield (Ali Larter) struggle to stay alive in the zombie-infested wastelands. Alice joining the group and the news of Arcadia come as a spotlight through the darkness, but with only meager gas and canned food and vehicles with Mad Max-style makeshift armor, the survivors are left wondering how to reach the safe haven.
While Alice and her crew work to figure out a way to Arcadia, Umbrella scientists in an underground laboratory begin running experiments on domesticating zombies. One of them, Dr. Alexander Isaacs (Iain Glen), needs Alice's blood to concoct a new strain of the T-Virus—and it just so happens that Alice is in the "neighborhood"...
The film also stars Ashanti as Nurse Betty, Christopher Egan as Mikey, Spencer Locke as K-Mart and Jason O'Mara as Albert Wesker.
Resident Evil: Extinction contains examples of the following tropes:
- Aborted Arc: The end of the last movie had Alice being rescued from an Umbrella Corporation facility by her friends — only for the twist that Umbrella had let her escape, and were actually controlling her as a sleeper agent. None of this comes up in the sequel.
- Adaptational Location Change: Not in the film proper, but DeCandido's novelization mentions that Raccoon City is (or rather, was) situated on an island near California, whereas all the subsequent film and game installments instead placed it in the mainland United States.
- After the End: The T-Virus has contaminated and destroyed nearly all life on Earth since the last film.
- All There in the Manual: Keith R.A. DeCandido's novelization of Extinction clears a lot of things regarding plot points:
- The T-Virus pandemic is given much more attention, complete with early stages of the outbreak, as well as Jill, Carlos, Alice, and L.J having to survive before and after the outbreak, as well as explores the Detroit raid which led to Alice splitting up from the group.
- At some point during the pandemic, Carlos and L.J. formed up a "strike team" consisting of surviving police and military personnel in an attempt to fight off the undead and save as many people as possible. It ended poorly, with only Carlos and L.J. themselves making it out alive.
- The fate of Angela Ashford, last seen at the end of Apocalypse, is also revealed: Dr. Isaacs uses Umbrella's cybernetic control over Alice to force her into bringing Angela to him. He reveals that Angela's blood is of no use to him—her T-Virus strain is different from the one ravaging the world—and orders Alice to kill Angela. Alice puts a bullet through Angela's head and promptly snaps out of Umbrella's control.
- Alternative Foreign Theme Song: The Japanese version of Extinction uses "Last Angel"
by Koda Kumi as the theme song. - Apocalypse How: Class 3, in progress.
- Artistic License – Biology: Dr. Isaacs becomes bent on capturing Alice in order to use her DNA for his zombie experiments despite the fact that, by all reasonable logic, he should already have her DNA if he can create perfect clones of her (who somehow even display the same physical training as her). Isaacs does mention that he can recreate Alice's DNA, only it's not as "pure" as the original they are based on, but this explanation doesn't do much better.
- Asshole Victim: No one sheds a tear when Alice breaks one rednecks's neck with her legs and later gets the rest torn apart by their own zombie dogs.
- Attempted Rape: Some post-apocalyptic rednecks set up a fake Distress Call which ensnares Alice. They looked as though they were about to rape her until she neck snaps one of them and they decide to feed her to the dogs.
- Audible Sharpness: Alice's knives.
- Badass Longcoat: Alice rocks a particularly awesome one throughout the film.
- Big Bad: Dr. Isaacs serves as the primary antagonist of this film after having a minor role in Apocalypse.
- Big Damn Heroes: Alice gets one when she shows up and uses her psychic powers to kill off the crows attacking the convoy.
- Bond One-Liner: When Dr. Isaacs gets sliced to pieces by the laser grid, the Alice clone says, "Yeah, you're the future, all right."
- Brainwashed and Crazy: In contrast to her having a Heroic BSoD in the movie, the novelization has Alice being ordered around whenever she is mind controlled by Umbrella, including killing Angie and her caretaker.
- Character Development: It may just be five years of surviving a Zombie Apocalypse, but LJ seems like a lot less of a "gangsta" and seems to take things more seriously.
- Death by Adaptation: Carlos survives the events of Resident Evil 3. He dies in this movie.
- Death by Irony: Dr. Isaacs spends all his time killing Alice clones and experimenting with the anti-virus. In the end, he gets killed by Alice clones and the anti-virus.
- Dual Wielding: Alice's paired kukri knives.
- Dub Name Change: In the Spanish dub, K-Mart's name gets changed to "Burger" and her finding place to a Burger King, as the Kmart brand is virtually unknown in Spain.
- Dwindling Party: This slowly happens to the survivors; the novelization goes even further with that and estimates that Claire's group once had sixty survivors, which dropped down to thirty and then further.
- Dying Moment of Awesome: Carlos blowing up a truck to take a whole bunch of zombies down with him while doing a J.
- Elite Mooks: Dr. Isaacs' enhanced zombies are faster, stronger, and supposedly smarter than the regular variety.
- Expositron 9000: The White Queen.
- A Good Way to Die: Carlos Oliveira is bitten by a zombie, so he decides to clear a way into Umbrella's desert compound for the other survivors. He does that by driving (and crashing) a tanker truck into a giant horde of zombies, then triggering an explosion that destroys a large portion of the zombie horde surrounding the compound. The best part? He finds a marijuana joint (well after the whole survivor convoy ran out of cigarettes) and manages to take a puff just before he blows up.
- Guns Akimbo: Alice wields pretty much all her guns this way. Unlike the prior film in the series, Carlos and LJ seem content to just use one gun.
- Hall of Mirrors: LJ ends up shooting at a zombie's reflection. The zombie was actually behind him.
- Heel–Face Turn: The White Queen technically undergoes one of these. It just barely qualifies as her programming was designed to prevent the spread of the T-virus and try to control the epidemic as best she could. As an AI, she has no loyalty to Umbrella beyond what is programmed into her. Since Umbrella didn't think to do this, she turns on them as she quickly concludes that Umbrella is only going to make the outbreak worse if allowed to continue existing.
- Heroic BSoD: Alice, though this is a result of Umbrella's mind control.
- Hologram: This is how the heads of Umbrella meet. Alice uses it at the end of the movie as well.
- Heroic Host: Alice and the T-virus.
- Idiot Ball:
- The world has been all but destroyed with a tiny population of still living humans remaining, yet Umbrella is still pissing about with bio-organic weaponry, hosting board meetings and generally acting as if they still had somebody to sell their products to. It's not until the last film that it's revealed all of this was planned.
- LJ deciding to hide his infection and put everyone in danger, despite being competent enough to survive for five years in a zombie apocalypse.
- It Can Think: After being injected with a serum from Alice's blood by Isaacs, some of the zombies regain the ability to remember and think, as one zombie remembers how to use a camera and a cell phone.
- Me's a Crowd: The third film introduces many Alices. The fourth film promptly disposes of them all.
- Mythology Gag: The book containing transmissions to and from Alaska is likely a reference to the many files players need to find in order to complete the games.
- Never Trust a Trailer: The trailer for Extinction started out with a commercial for Las Vegas.
- New Powers as the Plot Demands: The T-Virus, a virus that turns humans and animals into zombies, can now somehow also cause a severe enough global drought to destroy the flora and dry rivers and lakes in just some years. The consequences of this barely even continue on in subsequent films.
- Psychic Nosebleed: Alice.
- Psychic Powers: Alice gets these from the T-Virus.
- Quest for Identity: Alice has shades of this.
- Raising the Steaks: The crows.
- Reclaimed by Nature: The city of Las Vegas has been reclaimed by the desert after the Zombie Apocalypse picked it clean.
- Room Full of Zombies: The Clown Car trailer full of zombies.
- Scarf of Asskicking: Alice's badass scarf which she wears with her equally badass duster jacket.
- Shown Their Work: Not perfect, but the film does show what a years worth of post-apocalypse decay can do. For example, parts of Las Vegas are engulfed with sand due to frequent sandstorms in Nevada.
- Shut Up, Hannibal!: Alice to a mutated Dr. Isaacs: "You're just... another asshole."
- Sequel Hook: It ends with Alice finding the rest of the clones of her that Umbrella was using for their experiments... and they're waking up.
- Synthetic Plague: The release of the T-Virus in Apocalypse caused mass death by the time of Extinction.
- Viva Las Vegas!: The crew stop off here.
- Zombie Apocalypse: The film takes place five years after the first film right during one.
