The events of two novellas, combined into a collection, are chronologically connected. First, Lykov investigates a series of murders at the 16th All-Russian Industrial Fair in Nizhny Novgorod, and on the way home to St. Petersburg, another incident happens to him. On the train, Alexey Nikolaevich notices a very suspicious fellow passenger and, unexpectedly for himself, decides to switch to his own path—getting off with him right in the middle of the night. A dark stranger leads Lykov to a den, where a whole gang of killers lives under the guise of gamekeepers—and that’s where the seasoned detective gets trapped…