In the early 1990s, the Soviet Union is in crisis and on the verge of collapse. The security services work actively to save their own personnel. A KGB major, Andrey Kravtsov, is assigned to protect a valuable agent codenamed Sirius, who works in British intelligence MI-6. Posing as a secretary at the embassy, Andrey travels to London and unexpectedly learns that Sirius is a young attractive woman facing mortal danger. She has compromising information about a member of the British Parliament connected to the royal family. Kravtsov plans to evacuate the agent through a channel set up by his longtime acquaintance. However, he doesn’t take into account that in this unstable time even the most reliable ally can turn into a traitor.