Everyman Ben Stiller suffers when his goofy best friend and next-door neighbor Jack Black grows insanely rich after inventing "Va-Poo-Rizer," a miracle consumer product that evaporates excrement -- until a chance encounter with a crackpot (Christopher Walken) convinces Stiller to seek revenge against Black's success. It's an easy premise but director Barry Levinson can't wring any humor from it. Envy lacks the edgy meanness that's part of that titular emotion; it wants to be nice, and nice is rarely funny. Stiller and Black act like their usually enjoyable comedic talents have been set on "lukewarm," and the film becomes a joyless, forced romp, with its sit-com mania pointedly underscored by irritating cue-music. Rachel Weisz and Amy Poehler have thankless, underwritten roles as the respective wives; meanwhile, Walken chews through his part with his usual inexplicable vigor. While everybody else deathlessly intones the unfunny words "shit," "poo" and "flan" repeatedly, you'll be aiming a can of Va-Poo-Rizer at the screen.