Redemption has a heaping-huge body count in Bruce Willis’ “Hostage,” whose passable opening and middle chapters promise a decent action thriller before all credibility is destroyed by the take-no-prisoners excess of the final act.

Willis, who hasn’t had anything approaching a hit in five years, returns to tried-and-true “Die Hard” mode as an ex-hostage negotiator forced to bargain and maneuver for his wife and daughter’s lives.

But this is “Die Hard” with a bullhorn as French director Florent Siri, in his English-language debut, apparently assumes American audiences are hard of hearing and doubles the decibels.

The explosions, gunshots, blows to the head and especially the uproarious score by Alexandre Desplat — which you’ll feel disagreeably rippling through your chest in the most strident sections — all are cranked to ridiculous volume to complement the overblown action.

After a painful opening-credit sequence booming with Desplat’s bass notes, “Hostage” settles into a fair little cop drama for a time.

Willis plays Jeff Talley, a crackerjack L.A. hostage negotiator with the long stringy hair, grizzled beard and laid-back demeanor of a former Grateful Dead groupie. When his latest case, a jealous hubby holed up with his wife and son at gunpoint, ends tragically, Talley packs it in, shaves his head to Willis’ familiar chrome dome, and takes a job as police chief in a sleepy California community where he prays every day will be “low-crime Monday.”

A year later, three punks in a battered pickup — semi-deranged Dennis (Jonathan Tucker), his levelheaded brother, Kevin (Marshall Allman), and seriously deranged buddy Mars (Ben Foster) — see an SUV they really like and follow it home.

A silent alarm and two gunshots later, one of Talley’s cops lays dead and the punks are holding widower accountant Walter Smith (Kevin Pollak) and his son and daughter captive in their lavish fortress of a mountainside home.

In Hostage, Bruce Willis, right, plays Jeff Talley, a former LAPD hostage negotiator who gets pulled back into action when he's forced to bargain and maneuver for his wife and daughter's lives. He's pictured with Jonathan Tucker, who plays kidnapper Dennis Kelly.

Unable to stomach another standoff, Talley turns command over to county sheriff’s officers and flees the scene. He’s almost immediately — and absurdly — dragged back in by masked gunmen who grab his wife and daughter, threatening to kill them unless Talley resumes command and obtains a DVD hidden in Smith’s house that contains vital organized-crime financial data.

From here, implausibilities mount exponentially, the characters become dumber and dumber, and the action hurdles to preposterous limits.

Adapted from Robert Crais’ novel by screenwriter Doug Richardson, who also is working on the script for Willis’ fourth “Die Hard” flick, “Hostage” devolves from the merely farfetched to action so lurid it’s practically demented.

In the span of a couple of minutes, director Siri hurls Molotov cocktails, immolations, barrages of bullets, rappelling G-men and other frenzied action on to the screen. The bodies pile up so fast, it’s hard to tell if anyone but Willis is still standing.

Hostage*1/2 Find showtimes, trailers and more on the movie

At this point, Willis probably could do the stoically reluctant hero thing in his sleep, which seems to be what he’s doing here (his trademark smirk is particularly off-putting shortly after his cop is slain).

The supporting cast is forgettable, save for Foster, whose attempts at playing the restrained wacko come off like a burlesque, as though deadpan comic Steven Wright were having a go at looney gunman.