Three super-heroines invite Supergirl to their home planet of Feminax, where Supergirl is revered. However, the girls (and everyone on their world) are really evil and use Supergirl to help them revive three of the most evil women in Earth's history, so that Feminax can conquer the universe.
Superman and Batman trick Lois into thinking that Bruce Wayne is Superman. She sets out to get to know Bruce better and nearly marries him until Superman shows up at the wedding and she calls it off.
Lois and Jimmy go to Herko's dimension to try to stop him from waiting for Lois. She convinces Jimmy to court Herko's neighbor Zagga to make him jealous.
On the planet Feminax, the Sisterhood of Evil hypnotizes Supergirl and forces her to commit evil deeds, culminating in the poisoning of Superman, but fortunately Comet is able to intervene and reverse the effects with the help of Circe.