The train has derailed. Above the scene of the crime, a talking cuckoo named Koukuyev flies on a balloon. He is a suspect and forced to provide evidence to the investigator. Koukuyev's life is a series of bizarre and absurd situations from which he suffers. The hero's excuses seem fantastical and plaintive, but they don't help the case. The stern investigator doesn't believe his stories until he himself is convinced of the strength of the "cuckoo's" anomalies.
