S5, E20: Phyllis breaks bad on Samantha's family, and Serena shuts her up by turning her into a cat! Miss Parsons finds Phyllis as a cat and decides to keep her. Meanwhile, Frank is looking for Phyllis and Samantha finds her at Miss Parsons' house with a whole bunch of other cats she has collected! She then finds cat Phyllis and gets Serena to change her back to a human.