Want to go back in time? Climb in mysterious dungeons in full digger equipment? See the world of the nineteenth century, get used to it and spin in a whirlwind of adventures? Then go there, and better - with the whole family, do not hesitate! No intertemporal portal? But the heroes of the book have it! One misfortune - the head of the family completely overlooked that the boys may have their own views on how to behave in someone else's time. And now the art of fourteen-year-old Ivan and his friend, a gymnasium student, has to be solved by adults! And the adults themselves - what to hide? - sometimes they behave carelessly and inattentively. Once on the verge of exposure, one can only rely on friends, especially since the key to the secret of the artifact that opens the passage in time is very far from Moscow...