When director Tex Avery left Looney Toons to work at MGM, there was a marked change in his work. Suddenly, his cartoons had an insanity to them that set them apart from his peers....and his MGM films are classics. Just watch "Swing Shift Cinderella", "Bad Luck Blackie" or "Little 'Tinker" and you'll see what I mean...he was responsible for the strangest, funniest and most surreal cartoons of his age. However, compared to these bizarro films, his "Slap Happy Lion" is amazingly normal.
The story begins with a lion being carted from the zoo to the booby hatch. Then a small mouse explains what brought the lion to this point....and the short consists of this same mouse terrorizing the lion...much like Jerry the Mouse terrorizes Tom the Cat.
This is a good film despite its lack of weirdness. Worth seeing.