Hippety Hopper escapes from a zoo, and when Sylvester first sees him, he believes that the kangaroo is actually a king-size mouse. A bulldog tries to convince the cat that there is no such thing, but when he too sees Hippety Hopper and his mother (who was searching for him), he and Sylvester hitch a ride on the Water Wagon.
The song playing on the opening titles is "You Never Know Where You're Goin' Till You Get There", which had been sung by Sylvester a few weeks earlier in Back Alley Oproar. The same opening title music would be used for Hippety Hopper the following year.
Also, Hippety Hopper is called "Junior" for this short only.
The cartoon was reissued with a Blue Ribbon on June 4, 1955 during the 1954-55 season.
The bulldog in this cartoon would later reappear in Hippety Hopper the following year.