As the crowd was leaving an advance screening of "There's Something About Mary," a guy in the lobby was passing out bottles of hair gel with the name of the film on the logo. The stuff was free, so why not? Everyone grabbed, a few laughed, some tucked the bottles into their handbags and jacket pockets. But a few groaned aaaargh and tossed the stuff into the trash without smelling or trying the substance. Why the overreaction? The "hair gel" is the movie's biggest joke, or, more accurately, the grossest sally. It's the gag that everyone will be talking about. If this movie were up for an Oscar (which is doubtful), this is the sort of thing that the Academy would remember at voting time even if the film had opened thirteen months before the poll. When Mary (Cameron Diaz) accepts a dab of the gel from Ted (Ben Stiller), who is madly in love with her, and places it on the front of her sunshine-bright blond hair, the audience roars. Why? You'll have to see the movie, though it's likely as not that your pals already spilled the beans (so to speak).

They always tell us in film school about the critic who roars with laughter, and while he's doubling up with mirth he's moaning, "This is awful, oh this is terrible, ah this picture is the pits." This is the kind of reaction this movie gives. The script has a few corkers and cases of multiple mistaken identities that you probably won't figure out. For the most part, though, its humor depends on the same sorts of gross-outs that the Farrelly brothers were noted for in their previous exercise in coarseness, "Dumb and Dumber." "Dumb and Dumber" has a plot that's similar to this one, also prominently featuring a dog (Jeff Daniels ran a dog-grooming service) and a bottle of beer which turns out to be not a bottle of beer. Like this, it involves a run-in with a gangster and a rendezvous with a cop. In fact Roger Ebert, who gave "Dumb and Dumber" only two stars, admitted that "there is a moment that made me laugh so loudly I embarrassed myself...I just couldn't stop." There's more than one twinkling just like this in "There's Something About Mary," particularly involving a dog which in one case reacts strongly to a tranquilizer and in another, to speed.

The sitcom plot revolves around an obsessive love that Ted has felt toward Mary for thirteen years. A student in a Rhode Island high school, he asks her to the prom, is amazed that she accepts, but then circumstances intervene which force him to cancel the date. Years later, he hears that she has moved to Miami and hires a would-be private investigator, Healy (Matt Dillon) to track her down. When Healy finds her, he also falls instantly in love and is determined to hide her existence from his client while he courts her for himself. The film follows the usual strategy of romantic comedy, which is to put obstacles in the paths of the lovers until the very end, when the relationship is consummated or at least confirmed.

There are two hilarious dog scenes. In one instance, Healy, using spy equipment, overhears Mary's neighbor Magda (Lin Shaye) insist that Mary accept as a boy friend only a guy who gets a friendly reaction for her Border terrier. This little dog has growled at every stranger who enters the house. To insure a cordial reception, Healy tosses a tranquilizer through the window, the dog eats, then passes out requiring Healy to administer artifical respiration, followed by electric shock stimulation. In a reverse situation, the dog has swallowed an upper and in one of the most riotous battles ever filmed between man and terrier, Ted is vociferously attacked, his reputation saved only when he ducks and the dog flies through the window. The most controversial scene finds Ted taking a certain action before a date with Mary, one which is designed to calm him down and which forms the basis of the hair gel joke. Yet another gross-out takes place when Ted gets a part of his body caught in the zipper of his pants just as he is to escort Mary to the prom and requires the help of Mary's mother, her stepfather, a fireman, a cop, and a team of paramedics.

Political correctness takes a vacation as the Farrelly brothers lampoon retarded adults and a cripple alike, while spoofing psychiatrists, gays, and obese women.

Like "Dumb and Dumber," the plot is pitched at the level of base, lewd and obscene films like "Mall Rats" and "Trainspotting," and should appeal mightily to high-school kids. That's not to say that adults will sit through the film with a straight face. This is the sort of picture that you can't help laughing with while realizing all the while that it's appealing to your basest stretches. In other words, you'll react just like the critics.