I'm not the other guy.

Mumbly (voiced by Don Messick) was a detective from The Mumbly Show". Mumbly bears an uncanny resemblance to Muttley from Dastardly and Muttley in their Flying Machines. Now he is the team captain for the Really Rottens. Work must've been slow for him ever since his show got cancelled. That is probably why he is a villain now.