Brave and quick-witted brothers Dima and Alyosha are traveling on a long-distance train. At one of the stations, another carriage is attached to the train - it transports the property of the circus tent. And from that moment on, mysterious incidents begin to occur on the train. The conductors disappear, the train foreman disappears. What mysterious force is behind all these incidents? Having made their way into the lead carriage, the door of which for some reason was not locked, they reached the driver’s cabin... and gasped - it turned out to be empty! And the train was rushing faster and faster...