When the Shark Men invaded Lemnos the Council ordered the women to go to work in the factory, producing Tridents, while the men did nothing. When Thoas, King of Lemnos, spoke up against the women's treatment the Council ordered that he be put in prison. In Rebellion on Lemnos, the women refuse to work in the factory any longer, just before they are due to complete a consignment of Tridents for the Shark Men. The Council of Four imprison all of the women and ponder their next move.

Triplos is the most hard line member of the Council. It was at his insistence that the women were imprisoned. Criesus and the unnamed member are non-committal, and it is only Bebos who sympathises with the women's plight. Their differences, however, pale into insignificance when the chief Shark Man cuts through on the communicator in the middle of the Council meeting to say that he is on his way to pick up the Tridents in person. Triplos quickly comes to his senses and orders that the women be freed.

Ulysses and Hipsipile, meanwhile, have already freed the women, who then confront the Council. The unnamed member tells the women that the Shark Men are on their way to pick up the Tridents, but the women are too angry to listen and a battle ensues. Ulysses intervenes and tries to reason with both sides. Triplos is resigned to his fate, thinking that they can do nothing but accede to the Shark Men's demands. It is left to Hipsipile and King Thoas, now freed from prison, to explain how they can defeat the Shark Men by luring them into the factory and jettisoning it into space. It can work only if the men and women put aside their differences and unite against their common enemy.