Set in the turbulent years surrounding World War II, Season 1 follows Major Nikola Deyanov—codename Sergei—as he leads the fight against fascism in Bulgaria. Haunted by the childhood memory of his father’s murder, Deyanov trains in Moscow before returning home as a Soviet intelligence operative determined to pursue the “enemies of the people.” Opposing him is Bogdan Velinsky, a sharp and calculating officer inspired by the real-life police chief Nikolai Geshev. Their ideological conflict drives the series, portraying two men bound by duty yet divided by belief. With strong performances, high production value, and a tense cat-and-mouse dynamic, the first season explores themes of loyalty, conviction, and the human cost of political struggle.

Season 2 unfolds over 13 episodes and takes the story to a broader stage. Velinsky, now head of an international spy network working to destabilize Bulgaria’s new order, remains Deyanov’s elusive adversary. Under the command of Bulgarian counterintelligence, Major Deyanov and Captain Bombov race to uncover and stop the spies and saboteurs sent by Velinsky and his foreign allies.