When in doubt, go for the fart jokes. Better yet, team the ultimate nerd (Eugene Levy, as a dental equipment salesman) with the ultimate hardass (Samuel L. Jackson, as a grouchy federal agent). Have them meet accidentally, take turns calling the other my bitch, and go after some killers. The only characters in this formulaic crime comedy that I halfway liked were a couple of barely glimpsed wives, but the two leads keep it going through sheer determination. Les Mayfield (Flubber) directed. PG-13, 84 min. (JR)