Svetlana, young pretty girl, works as a trolleybus driver in a small town and almost all her permanent passengers are at least a little bit in love with her.

A dangerous patient escapes from a specialized psychiatric clinic — a former Soviet intelligence officer and traitor named Tsventukh. Once free, he begins to take revenge on Matveev, the man who put him behind bars. After losing first his wife, then his friends, Matveev realizes that from now on, he can rely only on himself.

A daring assassination attempt is made on a prominent businessman and public figure. As the investigation unfolds, it becomes clear that a deeply covert militant organization is operating in the country, made up of intelligence agency personnel. Matveev's old friend, General Sokolovsky, asks him to infiltrate the organization.

On Belgian territory, a unique emitter is being developed under the supervision of a Russian scientist. The lives of many are at risk, as the device can disable any mechanism running on liquid fuel. Matveev must track down the international terrorists to prevent a catastrophe...

Military journalist Igor Vladimirov turns to his longtime friend — intelligence colonel Sergey Matveev — for help. Fifteen years have passed since they last met. A quarrel over a woman named Zhenya, whom Igor eventually married, drove them apart. Reluctantly, Matveev agrees to let go of past grievances and visit Vladimirov at his country house.

In one of the chemical laboratories in Switzerland, controlled by the CIA, work on a deadly virus — intended for military use — has been completed. Russian intelligence agencies take a special interest in the development and assign mathematician David Bronstein to obtain a sample of the potential chemical threat.