The Hive, this is the place where the film begins. This place is a top secret research laboratory owned by Umbrella Cooperation.
A man loads a T virus and its remedy into a case and drops a flask containing the virus into the lab. Minutes later, the virus spread throughout the whole laboratory trough all means and resulted in the death of all the people present there.
Somewhere else wakes up Alice in an empty mansion. She has forgot her own identity. She is suddenly taken into custody by some commandos. Later on another man Spence is discovered unconcious and looking at her Alice remembered having seen a picture of herself with that man and from the picture it looked like they were married to each other. The picture was the property of umbrelle cooperation. The man Spence was also suffering from amnesia.
They are taken into an underground train station. The 'One' as he is known is the head of the commando force and explains that Alice, Spence and the whole commando force works for the umbrella cooperation. THey were sent here to investigate why the Red Queen killed all the staff and people there. She was the one who released the nerve gas responsible for the amnesia of Alice but as time goes on Alice starts to remember of her past.
Once in the underground laboratory they witness all sorts of strange experiments conducted on humans and animals. Later on in the film thye are attacked by some strange sorts on walking dead humans "Zombies". They also have to face a deadly monster which was the product on umbrella's experiments. The infected humans and animals such as dogs became zombies and feed on flesh.
During the movie many commandos lose their lives and Alice starts remembering of everything. The managed to find that there is a cure for the T virus but by that time most of the members of the crew have already died or turned into zombies.
Matt another person that pretended to be a police was actually not one and was working with her sister on the t virus in order to expose umbrella cooperation but her sister died during the spread of the virus.
Later on they try to activate the Red Queen in order to help them find a way to escape and Alice somehow manage to convince her to help them. The biggest monster in the film is the licker. It managed to scratch Matt while they were trying to escape in the underground. Finally only Matt and Alice survived and Matt starts having a mutation. They reach the very same mansion and when they open the door, the are taken into custody by a group of scientists. They mention about putting Matt into the "Nemesis program". Alice tries to take down the scientists but fails to and as she fades down she hear them saying we are opening the hive. We need to know what really happened there.
When Alice woke up, she found herself in a hospital. She managed to find a way out and the hospital is completely deserted. As she makes her way outside, she cannot believe her eyes. The whole Raccoon City was abondoned with apparent sign of chaos everywhere. He takes a shotgun from a police car near her and the camera moves upwards showing the complete destruction of the city and the film ends.