A Night at the Opera
This film and Duck Soup often seem to be in competition for the best Marx Brothers movie. Duck Soup may be the more respected and satisfying (by most people and from my perspective as well) due to it's more grandiose subject of politics and war, but A Night at the Opera just may have slightly more laugh out loud moments. Although, it's very close!
From the very first lines of the movie where Groucho as Otis B. Driftwood has been standing up Mrs. Claypool for lunch, the laughs just come nonstop. No one plays it better than Groucho. And when all three of them get together there's no stopping the laughs. And with most Marx brothers films you get a good taste of some decent music and signing as well.
In the contest for the funniest and greatest comedy of all time, I think this is the greatest contender.
Rating: 10/10