3rd Rock from the Sun - Season 6 Episode 18

With the identity of Scoochie revealed to be Liam Neesam, who had visited Pendelton three years ago, Dick is panicked, and follows Liam and Mary to dinner, where he overhears Liam offering her a job with a six-figure salary. The other Solomons suggest that Dick reveal himself as another alien in order to gain Liam's respect. When he does, however, Liam reveals that he doesn't care for Mary, but that she is part of a huge plan to transform the Earth's entire population into monkeys, and rename it Planet Monkey World, so that it may be an exhibit for aliens. Meanwhile, Sally, Harry and Tommy discover that their favorite movie, Arthur 2: On the Rocks' has a 'prequel' - Arthur.