Exciting stories based on factual medical material, written by a practicing doctor. The anniversary meeting of graduates of the Medical Academy on a cruise ship promised to be joyful. Toasts, toasts, memories... But it soon became clear that behind the apparent cordiality and general fun lie long-standing grievances and rejected feelings. Surgeon Pyotr Frolov, considered the most perspicacious in the company, feels that the matter will not end with complaints alone. The trouble was not long in coming - on the night after the banquet, a brutal murder occurs. There is a quiet panic on the ship. It seems that old scores have been settled and there is nothing to fear anymore. But suddenly it turns out that a complete stranger was killed and, therefore, the nightmare will continue...