Ulysses and Yumi see a piece of her home world Zotra flying through space. Knowing it could revive her brother, Numinor, they follow it to a swamp planet, but are attacked by monsters that can take on any form - even them.
Yumi dreams about a strange coffin she opens with her flute playing. Just such a coffin leads them to the planet of the Sirens. But space pirates kidnap the children to force Ulysses and Nono to face the Sirens to get a map.
Ulysses and the children land on a planet which is similar to prehistoric Earth. There they meet a winged female called Sauria, whose people live in terror of the Keconopters - a race of strange mutant vulture-like beings.
Ulysses is lured to the planet of the enchantress Circe. She revives the companions, but turns them and the children into pig slaves. Circe sets them to work building a tower that will house all of the knowledge of the universe.
Princess Ariadne asks for Ulysses' help in saving her lover Theseus, as her father King Minos has sent him to the Labyrinth. The Odyssey sets off to the Labyrinth but will they be able to find Theseus before the Minotaur does?
'The Grandson of the gods' Mercurius asks Ulysses to go on a quest for him. The bubble-dwelling Mercurius wants Ulysses to steal a jewel from the brow of Atlas that would give Mercurius the power to send the Odyssey back to Earth.
The Odyssey picks up a distress call from Nereus, King of Nereopolis. His planet has been invaded and taken over by the Shark Men, his people enslaved and a mechanical tyrant installed. How can Ulysses help, when he is in prison?
The most powerful magician in the universe saves Ulysses from attack. The magician then breaks the curse of the gods, reviving Numinor and the crew of the Odyssey. However, in return he makes a terrible demand of Ulysses.
The women of the planet Lemnos are being forced by the Shark Men to build the Trident ships for the gods. Princess Hypsipyle of Lemnos asks for Ulysses' help. But the children discover that another group also lives on Lemnos.
The Odyssey is drawn off course and Shirka does not respond to Ulysses. They go to the planet of the machines which is ruled by Cortex, a tyrannical computer. Nanette, a female robot falls in love with Nono and helps them.
The Odyssey receives a distress call from Queen Calypso whose crystalline planet is under attack from Trident ships. She tells Ulysses that if he saves her planet she will tell him the way back to Earth, but can she be trusted?
Telemachus stumbles upon the Palace of Time and is sent 5000 years back in time. Ulysses has to follow him back to the Ancient Greece of Homer's original Odyssey and there meet the original Penelope, Telemachus and Ulysses.
When the central iris of the Odyssey is damaged in a meteor storm engineered by the gods. Ulysses is forced to travel to a world whose inhabitants are addicted to eating seeds which make them forget everything. Will he succumb?
Energy absorbing moths attack the Odyssey as it approaches the galactic glaciers. They meet Orpheus who asks to go with them to fetch his love Eurydice from the Kingdom of Hades. Hades offers Ulysses a terrible choice.