Enemy In-Law SpongeBob SquarePants : Season 4 Episode 10

Mr. Krabs' Mom is dating again, and it seems like things could be serious. Krabs tries to be happy for his mother, but he is absolutely horrified when he learns that the secret paramour is his arch-rival Plankton! Convinced that this just another trick aimed at getting the family formula for Krabby Patties, Krabs tries to reveal Plankton's schemes and breakup the ill-favored fling.