Captain Emelin, nicknamed Emelya, Captain Vasin and Dolbunov are investigating the most complicated crimes, and criminologist Masha Likhacheva helps them in this. Emelya's reputation is so-so, the head of the department, Colonel Khitruk, dislikes him for his independent character, but has to put up with him because Emelya has a good disclosure.

The year is 1953. Due to the mass amnesty, the criminal situation in the USSR is tense. At the same time, Ivan Astafyev, a former commander of a reconnaissance platoon, who was released from prison, returns to his hometown of Gorky. And immediately becomes a victim of an attack by bandits, and then a false accusation of beating the attackers. Ivan's pre—war acquaintance, Captain Shvedov, helps out of trouble, who gets him a job at the Dynamo sports society to train policemen in hand-to-hand combat.

An experienced virologist, Anya Markova, gives up her personal and professional life in Moscow and moves to work at a research center in Novosibirsk. She is clearly trying to escape from some personal pain, but in a new place fate throws the heroine another test - an outbreak of an unknown disease is recorded at the site of an illegal dump of a large meat processing plant in a remote village.

The year is 1967. A series of mysterious murders of women are taking place in Leningrad. An experienced KGB major, Chuzhbin, and a police captain, Fedorov, are assigned to catch a maniac who leaves mysterious signs next to the victims.

In the late 1980s, when “perestroika” was taking place in the USSR and the era of the Soviet Union was about to collapse, life became unstable and very different. The 1980s brought not only freedom, but also waves of crime on the city streets. While some young people began to ‘grow up’ on the streets, others found it difficult to find their place in this unpredictable reality. Andrey, lives with his mother and five-year-old sister. He studies at a music school and often encounters street teenagers who harass him. To protect himself, Andrey makes friends with one of these teenagers, Marat, who introduces him to gang life. Youth groups fight for every piece of territory; they defend their right to live the life, even breaking laws and promises. The only thing that matters to them is the vows they make to their gang members-brothers, with whom they confront the violence and fears of the adult world.

Former boxer Egor Tarantsev arrives in his native seaside town for his mother's funeral. Twenty years ago, he left for competitions and never returned to these parts. His career took off, he turned professional from amateurs, fought for the championship title in Las Vegas, everything was going well in the ring, until one day the doctors gave Egor a verdict - if he did not stop, the consequences could be irreparable, from stroke to death.

The main character of the story is veteran officer Mikhail Samylov who loses his friend Igor Makarov in Syria. Mikhail comes back to his port hometown Yantarsk to help Makarov’s widowed wife. He blames Igor’s death on himself. He doesn’t know, though, that Makarov is actually alive and turns out not who he seemed to be. A small port town becomes a battlefield of life and death. A chain of crimes always leads to one man — owner of the port Kupriyanov. Lost at what to do with his life, Mikhail, tormented by the pangs of guilt, will have to solve the crimes and find a new reason to keep on living.

Major Oleg Gromov arrives in Beloyarsk, one of the biggest railway hubs in the country. He comes there to pay a visit to an old friend Vyshenkov, his former martial arts coach who now is the Head of the Security Department at the railway. Happy to see his old trainee, Vyshenkov promptly offers him to spearhead a squad of the Rapid Action Team (RAT) that was created to guard the rails from the rampant gangs. However, Gromov has his own plans for life: back in the capital, there’s an exciting and generously paid job waiting for him. But everything changes once Vyshenkov falls victim to a bandit attack. Gromov sets his mind on staying in Beloyarsk and becoming the leader of RAT. With the help of his new subordinates, passionate investigator Dmitry Kulikov, and psychologist Irina Tikhonova, he starts his own investigation of the railway case. He’s up to challenge a dangerous and invisibleenemy that is ready to do anything to silence the truth about the railroad affairs.

After a long absence, surgeon Maxim Mikhailov returns to his hometown to help his mother, who is suspected of having an early stage of Alzheimer’s. He gets a job at a local hospital, and on the very first day faces a serious test to operate a patient with a severe brain trauma. Maximov saves the girl, but when transferred to the nearby regional hospital, she dies under suspicious circumstances. The doctor launches his own investigation and finds out the dark truth behind the young woman’s death. It is the first case in a series of medical and criminal mysteries he is going to solve throughout the series. Maksimov is a talented doctor and a passionate person, but his methods are both outrageous and admirable. He keeps saving people’s lives performing the most challenging surgeries but, as it turns out, not everyone is happy about it.