It's not every day that you hear screams of laughter coming from a movie theatre, but you're likely to be hearing them for the remainder of the summer at venues showing There's Something About Mary, the latest comic assault on good taste and political correctness from the cheerfully vulgar and persistently shameless Farrelly Brothers.

Having debuted with the surprising Dumb and Dumber and stumbled with the hapless Kingpin, the all-purpose Farrellys-they write, direct, executive produce-prove to be third-time-lucky with There's Something About Mary. This is a riotous screwball comedy for the '90s that surpasses the tastelessness of the duo's first two movies-no small achievement-but also pays homage to the Marx Brothers, the Three Stooges and Preston Sturges. Not to mention a raft of urban legends, tall tales and dirty jokes that most of us have heard before, but never expected to see-often in graphic detail-on the big screen.

Obsession is a frequent theme in screwball comedy and here it centers around the beautiful and smart Mary Jenson (Cameron Diaz), a well-nigh perfect woman, whom we first encounter just before her high-school graduation in suburban Rhode Island. Mary's unlikely date for the senior prom is Ted Stroehmann (Ben Stiller), a nerd with a hideous wardrobe and a mouthful of braces, who can't believe his luck. But he believes it soon enough when he arrives at Mary's home to pick her up and manages to get a crucial part of his anatomy caught in a zipper that refuses to unzip-a dilemma that, unfortunately for Ted, quickly draws a crowd of curious onlookers, including Mary's parents, a fireman and most of the neighbors.

Years later, still woefully obsessed with Mary, Ted hires a shifty private eye named Healy (Matt Dillon) to locate her. Healy finds her in Miami and is instantly smitten. Back in Rhode Island, the gumshoe concocts a story about Mary being overweight and wheelchair-bound in a housing project and advises Ted to forget about her. Healy then returns to Florida, spies on Mary, and poses as her perfect man: an architect who works with the disabled and owns a house in Nepal. Mary, whose brother is mentally handicapped, falls for Healy's line. Meanwhile, Ted has learned the truth and drives down to Miami in hopes of a reunion. What he gets, following a hilarious run-in with a hitchhiker and a subsequent arrest on a murder charge, is more like a gathering of questionable suitors. This odd lot includes his best friend Dom (Chris Elliott), who is coming down with facial hives; Tucker (Lee Evans), a faux Englishman on crutches; and, of all people, Green Bay Packers quarterback Brett Favre, playing himself.

The sight of the unflappable Mary surrounded by dubious admirers is central to the formula that makes There's Something About Mary work comedically. As written by the Farrellys and as played by Diaz, Mary is not only beautiful, but clever, compassionate, understanding and sincere, qualities that, save for Favre who's simply doing a cameo, the men smitten with her lack big-time. In fact, each of them is so undeserving of Mary that the movie delights both in their inadequacy and their stubborn inability to acknowledge it.

While Diaz splendidly occupies the center of the film, it is Dillon's performance as the smarmy, thin-moustached sleuth that elevates There's Something About Mary to genuine screwball-comedy status. Healy is not above any ploy or double-cross, and a scene where he drugs a dog and then accidentally sets fire to it has to be seen to be believed, even if, as we're told, no animals were harmed during the filming. There's Something About Mary isn't for everyone, but those who miss it might be wondering all summer about a certain 'hair gel' scene that...well, you had to be there.

--Ed Kelleher