THERE'S NO SHORTAGE of science fiction that deals with humans wholly replaced by robots or replicants or androids (sexy androids), but the incredibly bloody and mostly great Repo Men slightly tweaks that premise. Of course, it's a tweak that's been tried before (by Repo! The Genetic Opera, of all things): In the not-too-distant future, organs are mass-manufactured, marketed, and implanted to keep people alive—but should a recipient default on the sizable payments, a repo man will show up and forcefully repossess the organ in question.

Remy (Jude Law) is one such repo man, and the film begins in a sly, blacker-than-black comic tone as he methodically guts the deadbeats who can't make their payments. One day, Remy's victim is music producer T-Bone (RZA), who, oddly, has just finished recording William Bell's 1967 soul classic "Every Day Will Be Like a Holiday"—in this movie's universe, that song doesn't come out until the future! Anyway, Remy suffers a heart attack on the job and wakes up in the hospital with a shiny new ticker, along with the attendant, exorbitant payments.

It's no surprise that Remy has a change of heart (eh? eh?) and can no longer continue in his line of work. Nor is it a surprise that his best friend and co-worker Jake (Forest Whitaker, as excellent as ever) becomes the one to try to track him down. Remy meets a fellow debtor (Alice Braga) who has received several transplants, and during the movie's muted, moody middle section they boringly explore their tender feelings and even tenderer organs.

But Repo Men gets good again during a brutally violent final act, as intrigue and loyalties and blood and organs fly all over the place. The twist at the very end smells like bullshit to me, but otherwise Repo Men is smart, grisly fun with a lot more to offer than gore.