OK K.O.! Let's Be Heroes - Season 3 Episode 6 The K.O. Trap
Overview: K.O., Rad, and Enid break into Boxmore to get back their doors when they find themselves in a box shaped room that does not have any doors or windows. As they wait it out, they begin to realize that something is not right. Rad and Enid are, in fact, replaced with goo clones and K.O. must now get to the bottom of this mysterious situation.