After Calibos killed Zeus's sacred herd of flying horses (except Pegasus), he is transformed into a satyr-like creature and exiled in a hideout in the swamps with his henchmen. In revenge, he decides to spread a curse on the city of Joppa and to send every night a Giant Vulture to capture the spirit of his former lover the princess Andromeda in order to give her a riddle to be solved by her suitors, but those who fail are burned at the stake.
One night, the Giant Vulture transports Andromeda's spirit to the swamps, without knowing they are followed by Perseus riding Pegasus. After they arrive, Calibos takes Andromeda to the hideout, where his henchmen are waiting for her. The Huntsman gives her a riddle, then Calibos tells her to go and the henchmen watch her leave their hideout.
The following night, Calibos goes to the lake to capture Pegasus with the help of his henchmen. He manages to catch him with his whip and the henchmen cast a net at him, subduing him. They bring him to their hideout and lock him in a cage under the surveillance of the Giant Vulture.
Much later, the henchmen stand guard in the hideout during Calibos's absence. However, Bubo suddenly arrives and terrorizes them, causing most of them to flee. He then pushes a torch on the ground to set fire to the hideout before releasing Pegasus.