The spaceship Enterprise under the command of Captain Kirk has embarked on a new mission. They need to receive the reports from Professor Krater, who lives alone with his wife on the planet Orin 7. Mister Spak lands on the planet with a team. However, one of the crew dies unexpectedly. The doctor had difficulty determining the cause of death. The killer is the professor's wife Nancy. The professor decides to lure a creature from ancient times to the planet with a time machine to save him. Omar, a tourist, is about to be married to a woman he didn't know at the time. During the wedding ceremony, the machine pulls Omar to Orin 7. The tourist thinks that Omar survived. But the adventure is just beginning.