What ever happened to joyously screwball comedies? Sure, once in a while a chaotic free-for-all like Rat Race will come along, but for the most part, fast-paced Marx Brothers-style farces are gone with the wind. One of the last pure examples may be What’s Up, Doc?, Peter Bogdanovich’s 1972 tribute to the great comedies of the ‘30s and ‘40s. This wacky sendup of every comedy cliché is what my mother would call a hoot from beginning to end, with Barbra Streisand and Ryan O’Neal leading a big and crazy supporting cast through all sorts of wacky gyrations.

When four people carrying identical luggage all check into a San Francisco hotel at the same time, you know right away that the movie will be driven by a big suitcase screwup. Uptight scientist Howard Bannister (O’Neal) is carrying a bunch of ancient rocks that he thinks emit interesting musical tones. Judy Maxwell (Streisand), a petty thief and mooch who is hanging around the hotel mainly to steal room service sandwiches, is carrying underwear. Another guest carries a load of diamonds, and the fourth has a stack of secret government papers. When everyone grabs the wrong bag, the comedy commences.

Howard’s biggest problem is fending off the fast-talking Judy’s aggressive advances, especially when his very nervous and rather frigid fiancé Eunice Burns (the late, great Madeline Kahn in her first big role) shows up and wonders who this other woman is. Judy’s comment: “Eunice? There’s a person named Eunice?”

Once all the major players realize they’re toting the wrong suitcases, the chasing gets underway. Along the way there’s a hilarious hotel banquet and a cocktail party that ends in a classic Hollywood pie fight. Really. Bogdanovich even has the audacity to stage one of those hotel hallway chases with everyone popping in and out of doors in fast motion. Such antics could easily fail, but somehow he pulls it off. For whatever mysterious reason, it’s sidesplitting funny. There’s also time to squeeze in a song by Streisand, but even that is played for laughs.

What would any screwball comedy be without a big final chase scene? And since we’re in San Francisco, hills will definitely be involved. At one point Howard and Judy find themselves wearing Halloween costumes and zooming down hills on a delivery bike that gets encased in a long Chinese dragon. As they head toward the cold waters of the bay they have to dodge workers who, naturally, are hauling big sheets of plate glass across city streets.

What’s Up, Doc? was Streisand’s first real chance to play comedy without all the trappings of the bloated blockbuster films that made her a star. She’s a winner here (and went on to try broad comedy again with similar success in For Pete’s Sake soon after). O’Neal is the perfect befuddled straight man, and Kahn, too, becomes an instant comedy queen with her supporting performance. What’s Up, Doc? is 90 easy minutes of big laughs. Sit back and enjoy.