Tom grows tired of Jerry constantly drinking from his milk bowl. Nothing that Tom can do seems to stop Jerry- even locking him in a safe. He concocts a mixture to get rid of Jerry, but when Jerry drinks it, he becomes extremely strong. Jerry takes advantage of his new strength and gives Tom a really hard time, beating his rival to a pulp…until the formula wears off, and he must rush out and get some more. In the end, Tom mixes another mixture and drinks it himself. Unfortunately for Tom, he grows so big that the process suddenly reverses, and he shrinks to be much smaller than Jerry- who starts chasing after him!