Aside from the obvious 'animal-shaped cracker', it is a genius musical comedy with the Marx Brothers.

Features Groucho as Captain Jeffery T. Spaulding, Chico as Signor Ravelli, Harpo as The Professor and Zeppo as Horatio Jamison. The plot revolves around a priceless Beaugard painting that is stolen and replaced with a forgery, then the forgery is stolen and replaced with a different forgery. Needless to say, wacky hijinks ensue. Like most Marx Brothers films, the plot is just something that happens between jokes, physical comedy, and piano playing.(a note for the uninitiated: the Marx Brothers were all extremely talented musicians)

Here are a few of the classic jokes:

While recounting his trip to Africa:
Groucho: "One morning, I shot an elephant in my pajamas. How he got into my pajamas I don't know."

Groucho: In a case like this, the first thing to do is find the motive. Now what could have been the motive of the guys who swiped the Beaugard?
Chico: I got it! Robbery.
Groucho: Would you mind going out and crossing the boulevard while the lights are against you?


Quotes and character names from http://filmsite.org/anim.html.