Rare materials go missing from the archive. A conflict arises between two researchers—Ozerov and Rozhkin—over these missing materials.

The film takes place during one day of operation of a railway line, the capacity of which is lower than necessary. A disaster occurs: a passenger train crashes into a tank train, the driver's assistant is killed, and traffic on the section is delayed. The film explores the patterns that led to the accident.

It's a good thing to wander through the forest. The sun is shining, the birds are singing, the flowers and berries are blooming... It's a good thing! But the Drummer, who was not afraid of anything, found himself in a different forest, where there was no sun, only fog and darkness, and instead of birds, there were ghosts fluttering around, and evil spirits were screaming in inhuman voices! Witches were chasing him, giants were trying to trample him, and a dragon was trying to eat him. The Drummer's bride had been turned into a cuckoo! Anyone else would have run away from such dangers, but the Drummer did not. He had achieved everything he wanted...