Prokofy Gelikanov even manages to organize a traditional pre-wedding bachelor party in such a way that it turns out flawlessly. Pleased with how decorously and nobly the event was held, Prokofy returns home, and there is a stranger sitting at the table, killed with a knife in the back! The time of death coincides with the moment of Prokofy’s return; the lock on the door was opened with “original” keys. Poor Gelikanov will have to answer for a crime that he did not commit, unless private detective Miroslav Volgina finds the real killer...