Based on

Movies like The Long Road Through the Maze (1981)

The protagonists of the film, chekists Sasha Sizov and Ivan Shagin, take the confiscated jewels out of the city captured by the White Guards and deliver them to Kiev. Having returned to the city liberated by the Red Army, they expose a White Guard agent who has infiltrated the Cheka and take part in the defeat of Colonel Sherstev's gang.