A squad of U.B.C.S. commandos led by Klaus are sent to Raccoon City to secure an important scientist, Dr. Cameron. Using a handheld computer to track her location, the men are drawn to a warehouse in search of her, where a monster takes them by surprise and kills Roberto, one of Klaus' men. The team respond by killing it, but its DNA spreads onto a cockroach, which listens into the squads conversation.
It then finds a rat and infects it, the rat follows the remaining Umbrella team of four outside where they leave in their Humvee. It then infects a wounded crow, thus giving it the ability to fly and follow the U.B.C.S. They stop at a manhole where Dr. Cameron's signal is strong and two of the squad members, Norman and Roger, accompany Klaus into the sewers, and breach a wall where her location signal is strong with Ed left to stand guard outside. They find only Dr Cameron's equipment in the space where her signal is, and a zombie dog, which they shoot dead when it jumps at them.
Meanwhile on the street, Ed was killed by the infected crow. When the other two squad members investigate what happened, it kills Norman when he came up from the manhole. Now hosting a human's body, the monster chases the remaining squad member, Klaus, without Roger.
Klaus runs through the sewer with the monster in pursuit. He soon comes to an open hole in the wall, which he jumps through. Because the monster cannot fit through it, this buys him a short amount of time before it collapses the whole wall. He runs up a nearby manhole, where he is approached by several zombies, which he kills. The monster then comes up the sewer, destroying several zombies in the process. As Klaus attempts to run, it is able to stab Klaus in his heel with a tentacle. Before it is able to kill Klaus the driver of the Humvee, Roger, buys him some time to get in the truck. Klaus manages to make it before the monster comes after them again, and they make it out of the city by gunning it down with the Browning M2 .50 caliber machine gun mounted on its empty cab. Klaus wakes up a short time later in the front seat of the car. The time appears to be morning, judging by the sunlight. Klaus thanks Roger for saving his life, but Roger is silent. Klaus asks about the virus, and Roger explains how it moves among life forms, thus making it almost impossible to destroy. At this point Klaus sees a cockroach crawl into Roger's ear. A tentacle then bursts from his chest.
At this point Roger is revealed to have two faces, the second one being Dr. Cameron's. Cameron/Roger explains that she was watching them in the warehouse, in the body of the dog they later killed. She realized that Umbrella were after her research but she tells Klaus that he and the U.B.C.S. members turned out to be perfect "guinea pigs" for the virus she had created. When they killed her, she infected a cockroach, and then infected Roger when he was copying files from her computer.
She then tells Klaus that she will be able to look normal and always get away from Umbrella. She delivers the final line of the film: "Umbrella will never get their hands on my research". She then uses her tentacles to pull Klaus' face apart, and the film ends.
Quelle: wikipedia.com
