A mouse is attempting to commit suicide, but is stopped at the last minute by a baby kangaroo named Hippety Hopper. The mouse makes a deal with the kangaroo, that he will release him, in exchange the kangaroo will terrorize the mouse's tormentor a cat named Sylvester. He does so by making it look as if vitamins have enlarged the mouse. Sylvester attempts to fight the mouse, but loses and gets set to a ravaging Bulldog. The bulldog tries to fight the kangaroo but the mouse bites the bulldog on the foot and the kangaroo kicks the bulldog out of the house. The bulldog and Sylvester leaves the house and go ballet dancing.
When this cartoon aired on the FOX Network as part of their compilation show Merrie Melodies: Starring Bugs Bunny & Friends, the entire opening sequence of the mouse contemplating and about to commit suicide, only to be saved by Hippety Hopper was cut, making the cartoon start at the point where the mouse lets Hippety out of the crate.