Andrei Kozyrev who was unjustly imprisoned with the help of his former boss breaks from jail and becomes secret agent under the name Andrei Zotov. His goal is to find the source of the virus killing hobos.
People from management of Samsonov's genetic research center commit suicide one by one. The suspicion raises that Samsonov may be alive. Andrei meets Nastya who looks very much like his dead wife.
Cash-in-transit service was robbed. Andrei takes part in the investigation about missing money. His former cellmate in jail, Tsapa, who served time for forgery helps him.
Samsonov is experimenting with the virus. A lot of people gets infected in the city. Nastya wants to become Andrei's assistant but he's worried about her.
Scientist Orlovsky who knows the structure of the virus escapes from the mental institution he was held in. He infects Samsonov with specially mutated version of anthrax.
Now Nastya is the Samsonov's hostage. She is infected with the new virus and dying. Andrei forgets the grudge and tries to save the her no matter the cost.
Samsonov intends to sell the Lenshin's virus to Black Mansur. But the virus need the real trial. Samsonov is preparing the terror attack on the railroad.
Samsonov kills the real Mansur when he arrives to Moscow. Samsonov then kidnaps Sveta who was returned from America. Andrei comes into a clash with the villain.
