Portrait of Tommy as an Old Man 3rd Rock from the Sun : Season 3 Episode 18

Tommy is tired of being treated like a kid and decides to retire so that he can act the age he truly is (being the oldest of the group in alien form). At work, Mary reveals to Dick that she'd always dreamed of being a torch singer, so he decides to try to help her realize this. Meanwhile, Don unwittingly ends up stealing one of Sally's panties, and makes a series of attempts to return it without being caught.