Hippety Hopper is a Warner Bros. Merrie Melodies cartoon directed by Robert McKimson and written by Warren Foster.

[3] A despondent mouse, contemplating suicide at the waterfront, is saved by a caged baby kangaroo.

They soon concoct a scheme to make Sylvester believe the mouse has grown to giant size by taking vitamins.

Despite Sylvester's attempts to defeat the "giant mouse," he fails repeatedly, being constantly beaten to a pulp by the violently playful joey, and drawing the ire of the house bulldog, who berates him for not doing his job right.

When the bulldog himself decides to intervene (and nearly succeeds as his larger build prevents him from being as easily beaten as Sylvester), the mouse bites him on the foot, distracting him with pain and allowing the kangaroo to kick the bulldog out of the house.