Die Frauen von Lemnos arbeiten als Sklaven und machen Dreizacke für die Haifischmenschen. Die Bewohner von Lemnos beschließen, die Haifischmenschen zu ködern, sie in die Fabrik zu locken um sie dann mit einem Schiff im All auszusetzen.
Passing a ringed planet that looks just like Saturn, the Odyssey receives distress signals from a disabled ship. Ulysses and the children rescue the pilot, and she tells them her name Hypsipyle is and she wishes to go to the base at Istria. She wants help in freeing the women of Lemnos, after all the men imprisoned them since they rebelled against their male masters. On Lemnos, it is the women who do all the work, and work in the factories producing Tridents for the Sharkmen. As punishment for her disobedience, the Lemnos Council of Four imprisoned Hypsipyle's father, the king of Lemnos. As Ulysses escorts Hypsipyle to Istria, she tells him that her father may know the location of the Kingdom of Hades. At Istria, they find the entire base has been destroyed by Tridents, so they then head off to Lemnos itself. There, they find the factories empty, with all the women still imprisoned. They free the women, but on board the Odyssey Yumi senses that they are in danger, and so she and Telema
En navigant près d'une planète ressemblant à Saturne, l'équipage découvre une navette en détresse, avec à son bord une pilote complètement épuisée. Une fois sauvée, Hypsie, habitante de la base de Lemnos, demande à Ulysse de l'emmener sur la base de Thrace, afin de la sauver elle et ses consoeurs, du joug des hommes de Lemnos qui les obligent à fabriquer les Tridents des monstrueux Hommes-requins...
En la órbita de un gran planeta negro hay dos estaciones espaciales gemelas: Tracia y Lemnos. Esclavizadas por los Hombres Tiburón, sus habitantes hacen piezas para los tridentes de sus naves de guerra.
