Charmed (1998): Season 7, Episode 6

7 - 6: Once in a Blue Moon

When a blue moon causes amok at the same time the girls are assigned a new whitelighter, thanks to the Elder's suspicion of Leo, trouble brews. Meanwhile, Agent Brody tells Paige of a powerful new threat, and Phoebe & Leslie confess their true feelings for each other as Leslie prepares to leave.