Daffy's house is being invaded by mice. He decides to get rid of them by sending them across the sea so some starving cats can eat them. He does this first by attempting to gain their trust, by pretending to be nice. When the mice fall for the trap, one of them telephones Speedy Gonzales for help.
Now aware of Daffy's scheme, Speedy has one to counter it. He tricks Daffy into jumping into a box of fireworks with a lit match, which injures Daffy. The mice fall for the trap again afterwards, but Speedy whacks Daffy's foot and the mice then go to the other side of a cliff to get away from Daffy.
Daffy tries one last scheme which involves catapulting himself across the gap between cliffs. It doesn't go so well and he is flattened. Speedy then tells the mice that they should send him overseas, hoping they'll be looking for "pressed duck".
Note
This cartoon reuses the animated flying sequence from Stupor Duck (1956).
References
^Beck, Jerry; Friedwald, Will (1989). Looney Tunes and Merrie Melodies: A Complete Illustrated Guide to the Warner Bros. Cartoons. Henry Holt and Co. p. 356. ISBN0-8050-0894-2.