A friend is spinning you a yarn — a fascinating, complicated beast of a story. But the party's too loud, and you only catch a few snippets. It's intriguing enough to suck you in, but confusing, fragmentary,  frustrating.

That pretty much sums up Live by Night, a Prohibition-era mob story about a charismatic, impeccably dressed Irish American bootleg-booze smuggler played to the hilt by Ben Affleck, who also wrote, produced, and directed.

A rambling, sprawling, octopussian narrative, Live by Night is an ambitious would-be epic about the minor (if loud) role played by organized crime in shaping the American story during the American Century.

Maybe too ambitious: Affleck's American tale has as many subplots as it does rat-a-tat tommy-gun murders.

The great gangland epics burrow deep inside you, getting under your skin. Not so Live by Night.

Bursting at the seams with stylized dialogue delivered machine-gun-style by stylishly clad dudes and undressed dames, it swirls by the viewer at great speed, but doesn't really touch us very deeply.

Overlong and with a protracted ending that never seems to get to the point, Affleck's film is a rather sad waste of terrific art direction and good performances from a coterie of supporting players that includes Sienna Miller, Zoe Saldana, Brendan Gleeson, Elle Fanning, Chris Cooper, and Robert Glenister.

Adapted from the Dennis Lehane novel, Live by Night features Affleck as Joe Coughlin, a WWI vet from Boston who rebels against his cop dad (Gleeson) by becoming a small-time crook. Rebellious to a fault, Joe is condemned to death by Irish mob boss Albert White (Glenister) for consorting with White's personal dame, Emma (Miller).

Joe vows revenge and joins the crew of White's sworn enemy, Italian mob boss Maso Pescatore (Remo Girone), and moves to Tampa to run Pescatore's rum-running operation.

Saldana is soulful and sexy as a Cuban refugee who falls for Joe, while Fanning turns in a heartbreaking performance as a popular evangelical preacher who mounts a campaign against Joe's plans to build a megacasino resort.

The two women introduce a whole new mess of themes and subplots that explore post-Reconstruction racism, the fate of Cuba, and America's commitment to religion.

Affleck does serious damage to the film's rhythm and thematic consistency by trying to cram in so much material. There are just way too many moving parts.

One wishes he had developed Lehane's novel as a miniseries, though one wonders whether any network would pick up a story that has so many of the same elements as HBO's Boardwalk Empire.

As it is, despite a ham-fisted voice-over narration supplied by Affleck that's meant to draw the pieces together, Live by Night remains a hopelessly confused collection of beautifully crafted scenes and set pieces. They're terrific on their own, but they have no inner cohesion.

Live by Night should be a good learning experience for Affleck, who already has shown remarkable talent behind the camera and has great potential. Next time he attempts a vast, swirling epic, he'll know to give it a center of gravity.