Several young people find themselves locked in a bunker. At the same time, a mysterious man informs an esteemed scholar, professor Radomskiy, that his daughter has been kidnapped and forces the father to go back to work. The professor is tasked with transporting a tube with a strange substance, but an unfortunate road incident sees the capsule fall down into the drains and into the subway air conditioning systems.
A mutating virus rampages through the population, causing massive casualties. The city is in panic, and an evacuation plan is put into motion. The young people locked in a bunker are trying to figure out why they're being held against their will. Mr. Glotov, the CEO of «Summit» corporation responsible for the development of a vaccine that would create a new race of people is informed that only young women seem to escape death after being infected with the virus. The order is given to find professor Radomskiy dead or alive.
After Jenya's death, panic grows into horror and despair. A rescue worker, Max, returns to Moscow to find his sister. Professor Radomskiy tries to escape his captors. Someone locks Ira and Mitya in the walk-in fridge. Max manages to find the last living doctor in the hospital his sister worked at.
In a fit of rage, Valera smashes all the surveillance cameras in the bunker. The «Summit» corporation board of directors is concerned with the virus leak. Glotov is convinced that the situation in Moscow plays to the corporation's advantage because they've never been this close to creating the «perfect human». Professor Radomskiy scours the city searching for Ira. When his and Max's paths cross, Radomskiy tells the young man about the «Summit» corporation.
A man stumbles into the bunker, covered in blood. The captives take his key to the bunker and escape. Once they reach the surface, a small group leaves on a scouting mission. Everyone they see on their way is dead. In an abandoned supermarket, they run into some strange young women who look like zombies who chase after the group.
The zombie women kill a group of soldiers with their horrifying wailing. One of the women is presented to Glotov who orders the start of intensive research. Back in the bunker, Irina and several others try to save the bloodied man by going to the hospital to get some blood for a transfusion. One the way their, the man tries to tell them something important.
The guys repair some cars to leave the city. Aijan is attacked by one of the mutants, but Valera manages to fend it off. Marina and Pasha still haven't come back so Nadya says it's not worth waiting for them. The group celebrates their upcoming journey.
Outside, Marina is shot with a tranquilizer gun. She wakes up in Glotov's laboratory. She recognises one of the lab assistants as Petya, her boyfriend. Sasha finds out that they've been locked inside the bunker as part of a secret project, run by the «Summit» corporation. Ira can't believe her father conducts experiments on humans.
Stas and Natasha, while looking for help, get into an accident, destroying their car. The rest set out to find Radomskiy through an underground tunnel system. Natasha is bitten by one of the mutants. Stas manages to escape and Petya finds Pasha inside the bunker.
Pasha asks everyone to meet up in the park before leaving town. Valera objects, but Ira convinces everyone to go. Once there, the group gets arrested. They meet Pasha inside the prisoner transport vehicle. Glotov gives orders to blast the city with ultrasound.
Glotov is told that the mutants have started to die out. Aijan is looking worse. Anatoliy, Professor Radomskiy's assistant, sneaks into the «Summit» corporation lab. Ira brings the group to her father. Radomskiy admits he doesn't have a vaccine yet.
Radomskiy tells the group about project «Cleito» and his attempts to stop it. The lab is captured by Glotov's people. Radomskiy claims he infected Glotov with the virus and agrees to provide the vaccine is Ira and the rest of the group are allowed to leave the city.