Muck Mucks About (AKA Don't Muck It Up) is the tenth episode of the twentieth season. It was written by Ali Crockatt and David Scott.
Bob and the team are working at the Zoo replacing Bella the elephant's enclosure to remind her of the wild. Muck and Scoop begin to prank each other, and Muck decides to hide inside the elephant house so he can jump out and surprise Scoop when Scoop passes by. But instead, Muck surprises poor Bella. Using ingenuity and roleplaying skills, Muck acts like an elephant and manages to calm the alarmed Bella down.