It is difficult to call the primitive era of human history a paradise like the biblical Eden. Instead of a quiet life, two tribes living along the banks of the same wide river face severe danger every day. The Chief's tribe is losing ground due to the weakness and inexperience of their leader, who wants to be a friend to everyone. But the tribe of "jerks", led by the Leader, is at the peak of its strength and lives in prosperity. Therefore, one of the Chief's hunters escapes to the competitors, and the Chief's people joyfully accept him. But few of the savages understand what is really happening on the other side.
Shurik is trying to bring Tsar Ivan the Terrible home with the help of a time machine. But the VPN on which the miracle machine runs constantly breaks down and moves the would-be inventor and the tsar to different countries and times.