Unceasingly vulgar and sporadically funny, this revenge comedy rests heavily on the shoulders of former SNL wiseacre Norm Macdonald. Mitch and Sam (Macdonald and Artie Lange) have been best pals since they bonded in the face of childhood bullying: Sam was tubby and Mitch was a wussy smarty-pants. Now they're grown-up losers, Sam's horny old dad (Jack Warden) needs a heart transplant and his doctor (Chevy Chase), who's got a pack of bookies baying for his blood, promises that if the guys get him 50 grand, Pops will get a new ticker. They decide to get the cash by exploiting their only asset: years of practice executing dirty tricks on behalf of the downtrodden, a skill they've heretofore exercised only on their own behalf. Their escapades are occasionally funny, but all too often driven by the juvenile conviction that anything even remotely connected with homosexuality is riotously funny, including a porno parody of Men in Black, prison rape, ass-grabbing school crossing guards, homoerotic frat-boy roughhousing, opera, homosexual dogs and the word "fruit." The interstitial scenes that punctuate the comic set pieces are dreary, and the movie includes a painfully unfunny cameo by Don Rickles as an abusive movie theater manager, as well as by SNL alumni Chase and the late Chris Farley. Farley plays a barfly whose nose was bitten off by a Vietnamese whore, and if you share the view that noseless fat guys are ever so funny, you'll probably have a good time overall.