“Whatever it is, I’m against it.” —Groucho Marx, Horse Feathers

On AFI’s list of the 100 funniest comedies of all time, 1935’s A Night At The Opera ranks 12th, second only to its predecessor, 1933’s Duck Soup ( No. 5), among the five Marx brothers movies on the list. (Incidentally, the other three, along with such stone-cold classics as The Lady Eve and It’s A Gift, rank below Arthur, so take that with several grains of salt.) It was selected for preservation in the fourth year of the National Film Registry, in the same wave that included the screwball standards It Happened One Night and His Girl Friday. It contains a few of the Marx brothers’ most celebrated sequences, like the brilliant stateroom scene, which piles 15 people and a steamer trunk into the smallest cabin on a transatlantic ship, and Groucho and Chico’s contract negotiation, a masterpiece of tangled legalese and ripped clauses. A Night At The Opera was a huge critical and commercial hit, and no less reputable a source than Groucho himself considered it and its follow-up, A Day At The Races, the best films they ever did.

It was also the beginning of the end for the Marx brothers.

Then again, at least it was the beginning of something. Two years earlier, the Marx brothers completed their wondrous five-year run at Paramount Pictures with Duck Soup, but only history would later judge it a triumph. (It’s my favorite comedy of all time, and one of my five favorite movies, period.) It was tepidly received at the time, attacked for its politics and poor timing in a period of national and global upheaval, and the brothers went their separate ways, with Chico and Groucho retreating to radio and Harpo performing in the Soviet Union after the revolution. The anarchy that so delighted audiences annually from 1929 to 1932—starting with The Cocoanuts and continuing with Animal Crackers, Monkey Business, and Horse Feathers—had unaccountably soured, and it didn’t seem likely that the vaudevillian mischief-makers could transition into doing another schtick onscreen. They weren’t writers or directors, and they weren’t character actors, either. The Marx brothers were the Marx brothers: That wasn’t going to change, so the movies had to change around them.

Enter Irving Thalberg, “The Boy Wonder,” who rose to head of production at MGM in the mid-20s, married the glamorous Norma Shearer shortly thereafter, and died of pneumonia in the middle of producing A Day At The Races at age 37. Thalberg more than resurrected the Marx brothers after they were left for dead; he brought them to MGM, the classiest of the major studios, home to a stable of big stars and production values that dwarfed what the troupe got at Paramount. Thalberg’s theory was that Groucho, Chico, and Harpo’s assault on propriety in all its forms—“Whatever it is, I’m against it,” goes one of my favorite Groucho songs—was a turn-off to audiences, who yearn for more sympathetic characters. His solution? To craft a story that would have the brothers helping other people—beautiful, talented MGM people—achieve happiness and success. In other words, they would act as supporting characters in their own movie, but get billed as the Main Event. The gambit worked in the short term, but crippled them in the long run.

The best that could be said about A Night At The Opera—and this is no small achievement, because the movie is very good, if not quite up to its vaunted reputation—is that Groucho, Chico, and Harpo squeeze in all the inspired antics the story will allow. As if to reassure the purists, the opening scene has Groucho, as Otis B. Driftwood (the Depression moniker to end all Depression monikers), taking the stuffing out of Margaret Dumont, his favorite haughty nemesis, here playing Mrs. Claypool, a wealthy dowager seeking to make a big investment in the New York Opera Company. Dumont moves the plot forward, as she often does in Marx brothers movies where Groucho alternately insults her and appeals to her largesse, and there’s no more elitist a target for their brand of lowbrow tomfoolery than the opera.

With a new season approaching, the head of the company, Herman Gottlieb (Sig Ruman), looks to secure the services of his supremely snooty tenor Rodolfo Lassparri (Walter Woolf King), but the fresh-faced Riccardo Baroni (Allan Jones) wants his chance at the spotlight, and he’s hired his best friend Fiorello (Chico) to represent him. After Harpo’s chaos agent Tomasso silently declares allegiance by bonking Gottlieb unconscious for his own amusement, Riccardo, Fiorello, and Tomasso sneak onto a boat headed to New York in Driftwood’s immense steamer trunk. From there, Driftwood, Fiorello, and Tomasso conspire to get Riccardo his rightful tenor spot alongside Rosa (Kitty Carlisle), the pretty soprano he adores. That sometimes means yielding the floor completely as Riccardo and Rosa belt out songs, splash around in the shimmering pools of each other’s eyes, and generally look beautiful together. Roger Ebert confessed to hitting the fast-forward button.

Thalberg thought the Marx brothers could get “twice the box office with half the laughs,” and was right in calculation, though it helps that they’re determined to make those laughs count. A Night At The Opera trades anarchy for structure, but discipline isn’t always an enemy to comedy. A standalone sequence like the stateroom gag is basically a film within the film, building on the fact that the stowaways have been crammed into the smallest cabin on the boat, and adding to the crowd a manicurist, an engineer, a cleaner, and waiters bearing platters mostly of hard-boiled eggs. As in their old Paramount days, the Marxes only needed the plot to suggest a theme (the opera) and take them to a locale (a boat), and they’re free to make mischief within that space. It’s glorious—and markedly isolated from the whole:

There’s no shortage of classic bits to follow: Groucho, Chico, and Harpo imitating three bearded aviators at a ceremony to honor an Atlantic crossing (Chico’s speech about the aviators’ frustrated attempts to fly to America is a nonsensical masterpiece); Chico and Harpo replacing the orchestra music sheets for Il Trovatore with “Take Me Out To The Ball Game”; an opera that doubles as a wacky Keystone Cops chase sequence in the rafters; and an elaborate sabotage to give Riccardo his big chance. Yet this last gesture sticks in the craw. For the greatest comedy troupe in screen history to exist in service of a would-be studio idol like Allan Jones is a compromise that opened the door to future compromises, and the eventual marginalization of the Marxes. Thalberg’s gambit was necessary to save their careers, but it led them permanently astray. (Room Service, the RKO comedy they made immediately after A Day At The Races, wasn’t even conceived with them in mind, and had to be retrofitted.)

All gripes aside, however, there’s one musical sequence in A Night At The Opera where Thalberg’s vision dovetails beautifully with the Marxes’ talents in a way that wouldn’t have been possible in the Paramount years. In the past, Chico and Harpo never needed to be charming and likable, much less “best friends” with a blandling like Jones. Yet the sight of Chico playing the piano for a happy scrum of children, clowning his way down the scales, is disarming and sweet, immediately followed by Harpo going from slapstick goofs on the piano to strumming a lovely rendition of “Alone,” the film’s romantic theme, on the harp. It’s arguably a cynical strategy to ingratiate the two to the audience, but it’s also a reminder that the Marx brothers were full-service entertainers who wanted nothing more than to please an audience in whatever way they could. And A Night At The Opera, for all its compromise, accomplished that without question.

Next: Zabriskie Point