During a combat campaign, the nuclear submarine K-119 suddenly moved in time and space, ending up off the coast of America in the summer of 1942. Having no idea how to get back, or even whether it is possible, the team decides to go to their native shores and help their ancestors win the war, especially since they are armed with the knowledge and technology of the 21st century. And so, one after another, the ships of the German fleet are sent to the bottom, the air base and port are destroyed. In the German headquarters there is panic, in ours there is bewilderment: someone is destroying the enemy, but who is unknown. Strange rumors just spread about a Martian submarine under the command of Lamipet...