Robert De Niro, left, stars as a harried movie producer and John Turturro plays an unhelpful agent in Barry Levinson's Hollywood satire What Just Happened. (Alliance Media)

Halloween is the perfect time to see a horror movie. How about one featuring a rampaging hulk of a movie star, a drug-crazed ghoul of a director and a studio boss who eats producers like muesli? Plus — horror of horrors — Sean Penn smoking?

What Just Happened, Barry Levinson’s fitfully funny satire of Hollywood, offers those chilling spectacles and more. The film, based on Art Linson’s tell-all memoir of the same title, stars Robert De Niro as Ben, a harried producer trying to grapple with the above-mentioned monsters, along with lesser evils like agents, screenwriters and ex-wives. As Linson and Levinson paint it, producing a major motion picture these days involves the combined skills of a babysitter, drug pusher, UN negotiator and fearless vampire killer.

We catch Ben in action as he’s putting one film project to bed and kicking off another. The first one, an edgy romantic thriller starring Penn, is getting thumbs-down reviews from test audiences — mostly thanks to its brutal ending, in which the bad guys shoot the hero’s lovable dog. Formidable studio exec Lou Tarnow (Catherine Keener) orders the ending recut before the film goes to Cannes. Its renegade British director, Jeremy Brunell (Michael Wincott), responds by throwing a coffee-table-trashing tantrum, showering her office with multicoloured M&M’s. It’s up to Ben to placate Jeremy with pills and sympathy as the devastated director hunkers down in the editing bay to mutilate his masterpiece.

Meanwhile, there’s an emergency situation on Ben’s new movie, due to start shooting in a few days: star Bruce Willis has shown up on the set overweight and sporting a beard of Biblical proportions. If he doesn’t shave it off, the studio will pull the plug on the picture. Ben dares to approach Willis with the ultimatum. Cue another, even bigger tantrum, as the burly actor goes Hulk, smashing up the wardrobe department. This forces Ben to seek recourse with Willis’s messed-up agent, Dick Bell (John Turturro), who has recently kicked an antidepressant dependency, only to wind up with debilitating stomach spasms that have him punctuating his phone conversations with agonized howls.

Ben wrestles with these crises while racing along L.A.’s endless freeways, a Bluetooth permanently hooked to his ear. (He’s so immersed in his work that his driving music is the eclectic soundtrack for the Penn film — everything from Ennio Morricone to Nick Drake.) In his few spare moments, Ben finds time to obsess over Kelly (Robin Wright Penn), his estranged second wife. He suspects she’s having an affair with Scott Solomon (Stanley Tucci), a screenwriter trying to pitch a movie set in a flower shop that he describes as “the Rose Bowl Parade meets The Da Vinci Code.”

What Just Happened, on the other hand, is The Player meets Entourage meets Speed-the-Plow meets Monster meets just about every other film, book and play about the machinations behind big-budget movie-making. The trouble with Hollywood insider tales is that they’ve all been told; Linson and Levinson are so late to the party, the caterers are already clearing up.

This film’s only raison d’être seems to be its special pleading for the role of the much-despised producer. “You’re just the mayonnaise in this rancid sandwich,” Willis growls at De Niro’s character. The remark is meant to be dismissive, but it’s actually pretty accurate, at least as veteran producer Linson sees it. The smooth Ben acts as the necessary adhesive that keeps the movie sandwich from falling apart.

Still, being a sucker for Hollywood horror stories, I rather enjoyed this latest exercise in self-mockery. Linson, who also wrote the screenplay, has a dry wit and a sharp ear for movie speak. Levinson takes a wry approach to Ben’s job, shooting it with the driving pace and tension-building score of a thriller, as if making movies was a life-or-death process. De Niro (who also co-produced) gives us a kind of cool, West Coast variation on Roy Scheider’s cranked-up Broadway choreographer in All That Jazz. The grizzled but dapper Ben subsists on espresso and Red Bull as he caroms from studio to nightclub to spa, making frazzled workaholism almost look glamorous.

A bearded Bruce Willis appears as a belligerent version of himself in What Just Happened. (Alliance Media)

There are pungent comic turns from Wincott as the Goth-y, drug-ravaged British auteur and Turturro as the agent suffering gut pains to rival Prometheus. (With his glasses and bow tie, Turturro can’t help but remind us of his screenwriter character in yet another Hollywood horror story, the Coens’ Barton Fink.) Willis provides an amiable self-parody, though he’s actually standing in for Alec Baldwin, who really did refuse to shave his beard for the Linson-produced movie The Edge. Penn, equally amiably, makes fun of his penchant for dark, edgy films à la 21 Grams, as well as his notorious need to light up in public spaces.

Levinson has an uneven record with satire. His last major collaboration with De Niro was the brilliant Washington-meets-Hollywood lampoon Wag the Dog (1997) — in which, incidentally, Dustin Hoffman played a movie producer ceaselessly touting his under-valued job. But when Levinson attempted a similar skewering of politics-as-showbiz with Man of the Year (2006), it fell flat.

What Just Happened, sticking strictly to showbiz, is much more successful, but it lacks Wag the Dog’s outrageous inspiration. And while it does a fine job of catching the eternal tensions between art and commerce, for an insider story, What Just Happened doesn’t go very deep. For one thing, we get no hint of what drives Ben as a producer, beyond a desire to stay a top player and get a coveted spot on the cover of one of Vanity Fair’s movie issues. If that’s the Holy Grail for Hollywood producers these days, it’s an even shallower industry than we thought.

What Just Happened opens in Montreal, Toronto and Vancouver on Oct. 31.

Martin Morrow writes about the arts for CBCNews.ca.