Penniless and hungry, Ren hatches the perfect plan: Stimpy can get work as a family's mouse-catching kitty, and Ren can pose as the mouse. What could possibly go wrong?

During the story of "The Littlest Giant," Ren drifts off and dreams that he is Wee Ren, a resident of Thumbsville who makes the mistake of befriending the littlest Giant, Stimpy.

Ren and Stimpy hit the road as door-to-door Rubber Nipple Salesmen, peddling their wares to a bizarre clientele, including a psychotic Fire Chief, a paranoid Mr. Horse, and a family actually in need of new nipples!

It's Ren's greatest scheme ever: switch places with a couple of babies and enjoy the pampered life. But being babies turns out to be harder than Ren or Stimpy ever imagined.

Ren has a new way to strike it rich - sell Stimpy's hairballs! Stimpy starts hwarfing hairballs on a production line, but what will Ren do when the supply runs out?