Superman saves Circe, who is a descendant of the original Circe, a Kryptonian scientist. Circe demands that Superman marry her, but he refuses, so she gives him some Evolution Serum, which causes him to morph into a humanoid Lion. Now Superman must try to adapt to society, looking like a Lion. Eventually Superman realizes that the serum has worked on him because it's laced with Kryptonite. he finds the antidote in the Kryptonian database in the Fortress of Solitude.