After the death of their newborn son, Lieutenant Colonel Ziganzhin and his wife Frida adopted three children. Frida instantly accepted and loved them, while Ziganzhin can’t make the children feel like his own— they don’t help ease the pain of their loss. And his wife now has no time for him; she’s absorbed in motherly care. To escape her longing, Ziganzhin actively joins the investigation of an explosion at the home of a famous professor—and it seems that other people’s family secrets will help him understand himself and rethink a lot.