A being claiming to be Apollo demands the worship of the crew and meets resistance.
A giant hand grabs the Enterprise as it approaches Pollux IV, where a being named Apollo says he is the Greek god and wishes to be worshipped. He chooses Lieutenant Carolyn Palamas as his mate, and Kirk must find a way to free the ship from his grasp.
The episode suggests that the gods of myth were really powerful visitors from space. Kirk argues that humanity has outgrown the need for gods. It is remembered for the ship held in a green hand and the sad farewell as Apollo's power fades.