Charmed (1998)

S2E5 She's a Man, Baby, a Man!

The sisters find out that Phoebe has a psychic connection to a deadly demon called a 'Succubus.' To draw the Succubus out, Prue performs a spell that transforms her into a man. At the same time, Piper stumbles upon a videotape at the dating service revealing that their new neighbor, Dan, has a romantic interest in her.