Peter is out riding his bike when he stops by an apartment complex, getting drink of water. The beautiful Allison comes out and asks him if Peter can help her with some things. Peter follows Allison into the building, then is talked into being changed into a woman for a little while, so Peter agrees. Peter then finds out that the woman isn't Allison at all, but now Peter is Allison, and he has to help Tom, who was in the body of Allison and who tricked him into entering the building, make certain that Allison is alive at the police station.
Mike keeps Peter, trapped in Allison's body, and keeps needing Peter to do some things for him, and Peter has no way to prevent or overpower Tom, so reluctantly, Peter does the things he is asked.
Peter finds the joys of being a female, as well as the hardships, and time goes on, with Peter still trying to get Tom to change him back into his male self.