Jason, a proven warrior, wants to experience more of life so foolishly accepts a wager from Pelias, king of a rival city, committing him to undertake a perilous voyage to obtain the fabled Golden Fleece from the little known land of Colchis far away to the east. Jason is, unknowingly, a pawn in the hands of Hera, wife of almighty Zeus, who intends to use him as a means to destroy Pelias.

Jason's father, Chiron, is owed favours by many heroes throughout the land so these men he calls upon to assist his son in the newly built vessel, Argo. Jason and his men become the Argonauts. Their long voyage is one of adventure and hardship until reaching Colchis, ruled over by its brutally sadistic king, Aietes. It is at the temple of bizarre goddess, Hecate, that Jason encounters her priestess and practitioner in the black arts, the young and beautiful Medea, who gradually takes over our tale. Only with her help can he overcome the gruesome, flesh-eating creature that guards the Golden Fleece but her price is his agreement to take her away with him and to later marry her.

After a dramatic escape from Colchis his restless crew, seeing they have gained little from their travels, demand Jason sails far to the west where they see an opportunity to gain plunder. More challenges face them at the island of Trinacria; Scylla and Charybdis, then the evil and deadly Sirens.

At last Jason and Medea are married and on reaching home, Jason defeats Pelias in a spectacular battle. Ever restless Jason afterwards insists they visit the large and powerful city of Corinth where they are welcomed by her king, Creon. There Medea, bearing Jason three children, practises her arts. But when Creon's seductive daughter, Creusa, comes of age, Jason sees her as a means of gaining power at Corinth and so rejects Medea in the girl's favour, making him unpopular with the people. At the new wedding, Medea, using her dark arts, exacts terrible revenge upon Creusa and so upon Jason. One day sitting forlorn by a fountain, Medea is approached by Aegeus, King of Athens, who realising her sadness and influenced by her beauty, promises to take her in should she ever need his help.

The people reject Jason, who is forced to quit the city, then Medea, with her children murdered, is also condemned to leave. Wandering and destitute she eventually reaches Athens where, true to his promise, Aegeus marries and makes her his queen. She later learns of the grim forfeit Athens has to make each year. She bears Aegeus a son, Medeus, who his mother is certain will in time become King of Athens. It is in Athens she learns the fate of Jason.

After five years a young man appears at court, the long awaited real son of Aegeus. Having foreseen his approach, Medea plans to murder him and as a result is banished from Athens, leaving Medeus to be adopted. In being banished her fate takes a most unexpected turn.