Take equal parts of "The Producers" and "The Gang That Couldn't Shoot Straight," throw 'em in the old story conference Cuisinart and turn up to 10. The result is "The Last Shot," a Mafia comedy about showbiz, with Matthew Broderick as a sad-sack wannabe movie director and Nathan Lane as -- no, no, that would be too much to hope for. The poor man's Nathan Lane, Alec Baldwin, is the producer.

He's also an FBI agent, which is the fulcrum of the story, said to be based on actual events from Your Friendly Federal Bureau of Investigation's files. Baldwin, in his bigger-than-life dese-dem-dose personality, is the feckless Joe Devine, a specialist in mob stings who, nevertheless, hasn't ever had that big, career-making bust and so is largely exiled to what the bureau used to call "the taco circuit": smaller, western cities where careers go to die, not prosper. But he has a bright idea.

Learning that a mob chief in Providence, R.I., routinely shakes down the few movie shoots that come to town and learning further that the mobster is a cousin to John Gotti, the No. 1 New York guy that everybody in the bureau is yearning to take down, he conceives of a clever sting.

He will pose as a movie producer, come to Providence with his production and ensnare the mobster (Tony Shalhoub); then, using that bust for leverage, he'll neatly turn the guy around to squeal on Gotti. In that way he'll nail the nation's top gangster but, far more importantly, he'll surpass his more successful brother (Ray Liotta), who's already a deputy director. (Sibling rivalry features prominently in the movie.)

The problem is that Joe doesn't know dink about movies. Well, why doesn't he spend 39 minutes on the Internet and become an expert like everybody else? The answer is that it's the early '80s -- the Gotti caper should have made that apparent -- and, hard as such a thing is to conceive, the Internet isn't in every home. So he flies blind, going to Hollywood. There, naive as an Iowa corncob in a Los Angeles Fatburger fryer, he sets himself up as a producer and looks for a project to sustain his fiction.

You have to say that Joe is pretty lucky. Instead of ending up busted and friendless, as have so many other similar pilgrims, he blunders into what seems to be the only decent human being in Tinseltown. This is Steven Schats (Broderick), already an executive in pictures. That is to say, he manages a movie theater. But, like everyone out there, he really wants to direct and, like everyone out there, he has a script. Joe, who doesn't know a script from a pail of water or a piece of cheese, signs him up; after all, it's a fraud, so what difference does it make?

The movie has one joke, but it's a funny joke. It's so funny it pretty much makes the movie work, even as it dribbles out to nothing at the end. The joke: Everybody loves the movies so much they want to believe.

The phony movie becomes more real than anything in the picture as the dreamers clamor to get close and sell their soul to it. It's like an aphrodisiac or some other form of intoxicant: Strong men of stern judgment and long experience fall all over themselves giving it up for "Arizona," to be shot in Providence. In fact, the lure of the Movie is so overwhelming that everyone thinks he knows how to make one of the damn things. Everyone -- FBI agents, mobsters, actors -- has one of those T-shirts around his soul that says, "Actually, I want to direct."

One of the great sources of humor in the movie -- that is this movie, not the movie within the movie -- is how everyone is aching to use inside movie lingo that they've picked up from "Entertainment Tonight"; these poor people almost seem to get a sexual charge out of deploying cliches like "How are the dailies?" and "I don't think the back story quite works" and "We need more product."

Meanwhile, as news of "Arizona" spreads, suddenly real movie people are showing up, because they want to be part of it. Toni Collette, slutted up like the hottest young actress in the biz, slinks her way into the picture and pretty soon has everyone wrapped around her little finger. Meanwhile, Baldwin and Broderick, the two decent men at the center of what is, after all, a conspiracy, struggle to deal with the temptations of "success." It goes to their head; they believe in it until it's all there is.

Jeff Nathanson, who wrote and directed, is a longtime movie writer (he wrote "The Terminal" and "Catch Me if You Can" for Spielberg) and really knows the business, and clearly he's connected enough to get a slew of name players to come aboard for outrageous turns. Joan Cusack has a hilarious spin as a TV producer who gives the boys some tips on the realpolitick of Hollywood; meanwhile Buck Henry, Calista Flockhart and Tim Blake Nelson play amiable grotesques in the "Sunset Boulevard" tradition.

Movies about movies usually amuse only the people who are in movies already. But "The Last Shot," despite its generic title and flat ending, tickles most of the way through.

The Last Shot (94 minutes, at Cineplex Odeon Dupont Circle 5, Cineplex Odeon Shirlington 7 and Landmark's Bethesda Row Cinema) is rated R for adult humor.

Matthew Broderick, left, is a theater manager who wants to direct and Alec Baldwin is an FBI agent who wants to make a career-defining bust.