"Oddballs and misfits" are Eddie Mannix's stock and trade. He babysits them on a movie studio backlot. Officially, Mannix is the head of physical production at Capitol Pictures, the fabled - and fictitious - dream factory of Joel and Ethan Coen's early-'50s Hollywood lark, Hail, Caesar!

Unofficially, Eddie, played with square-jawed gusto by Josh Brolin, is a fixer: the guy who keeps his pampered stars in line, or at least out of the scandal sheets. A water ballet beauty (Scarlett Johansson), pregnant and unwed, needs a husband, pronto. A singing cowboy (Alden Ehrenreich) needs a date, fast, and a dialect coach if he's going to make the move to sophisticated romances.

Baird Whitlock (George Clooney), the biggest star of all, needs help, too. He's been kidnapped by a gang of disgruntled screenwriters who happen to be ardent Communists. They're holding the dashing and slightly dim leading man hostage, and holding up production of the costly Roman Empire epic for which Whitlock is striving mightily to remember his lines.

The group of Marxist scenarists calls itself The Future, which gives the brothers Coen the opportunity to have a studio gofer pull up on his bike and chirp, "Mr. Mannix, I know it sounds screwy, but someone's calling from the future."

Hail, Caesar!, which happens to be the title of the film-within-the-film starring Whitlock and a cast of thousands, is a goofy conflation of Coenian elements: the numbskull huggermugger of The Big Lebowski, the La La Land surrealness of Barton Fink, the Old Testament overlay of A Serious Man. But the film, which looks great in a well-appointed, affectionately fake way, is not nearly as good as any of the above.

The jokes only go so deep, and the homages to vintage musicals (Channing Tatum in a sailor's outfit, tap-dancing on a bar) and grand costume spectacles (the sword-and-sandals Christ saga starring Whitlock) go only far enough to evoke a kind of kitschy nostalgia.

As the center of gravity in this exceedingly lightweight affair - an affair that boasts Ralph Fiennes, Jonah Hill, Frances McDormand, and Tilda Swinton among its cast - Mannix has personal dilemmas to contend with, too. A Lockheed executive has been dangling a generous job offer Mannix's way, a job that comes with none of the craziness of his current gig.

He could actually have time with his wife, his kid.

What's a studio fixer to do? (Mannix's name and metier are taken from the real-life and legendary figure, long in the employ of MGM.)

Well, what to do? Bark, brood, and bat around snappy Coen Brothers dialog, that's what. Hail, Caesar! may juggle some heavy stuff - God, Commies, Box Office Receipts - but no matter how hard Brolin's Mannix furrows his brow, it's impossible to take the guy seriously. Or to believe that he's taking himself seriously.

While comedies, by nature, require little in the way of seriousness, a little heft would be nice. Movies are "a ration of dreams for all the weary people of the world," somebody hoofing across the studio lot declares. But the rations are pretty meager this time around.