Professor Bug is an evil, greedy professor who works inside Mega City's Robotics Lab. He owns a robot named Rex.
Professor Bug is primarily blue. He wears a black suit embellished with a bug emblem. He also wears a pair of goggles and a silver hat made to look like a screw.
Pablo has played Professor Bug in two episodes of The Backyardigans: "Robot Rampage: Part 1" and "Robot Rampage: Part 2" from season four.