‘Donkey Punch’: Crimson Tide, By Kurt Loder

Low budget, high body count, not bad.

A “donkey punch” is a killer sex technique that, like the music of Kenny G, the books of Bob Greene and the thespian endeavors of Paris Hilton, is probably best heard about rather than experienced, since it can in fact actually kill. However much it may or may not occur in real life, this startling coital maneuver provides a serious jolt in “Donkey Punch,” a bare-bones British indie that offers more sweaty dread (and actual character development) than you’d expect from simple slasher trash.

The story begins in the Spanish resort of Marbella (looking laughably fake here, since the picture was shot in South Africa). At a raucous beach bar, three vacationing English sun bunnies — the lusty Lisa (Sian Breckin), the frisky Kim (Jaime Winstone, daughter of Ray) and the comparatively demure Tammi (Nichola Burley) — encounter a trio of fellow Brits: the hunky Marcus (Jay Taylor), the hulking Bluey (Tom Burke) and the comparatively demure Josh (Julian Morris). The guys are crewing for a wealthy yacht-owner, currently absent, whose boat is tied up in the nearby marina. They invite the girls aboard and introduce them to a fourth pal, the mild-mannered Sean (Robert Boulter). Soon the lines are cast off and the boat is cruising out toward open water.

Once the craft is anchored, booze and drugs appear, and a party gets underway. The talk turns to sex — specifically, the fabled donkey punch: a sock in the neck at a crucial peak of carnal frenzy. While Sean and Tammi chastely bond, the rest of the group heads belowdecks for more athletic interaction. There follows an unusually long and (for an R-rated film) graphic group-sex scene, during the course of which a donkey punch is administered and its recipient, not at all surprisingly, dies. What now?

Well, you know what now. The guys don’t want to get jailed for murder when they return to shore (the killing was recorded on a minicam, now mysteriously missing), and the girls aren’t likely to keep the deadly event to themselves. The rest of the movie is powered by claustrophobic menace and a notably effective score, by Fran├žois-Eudes Chanfrault, that features spectral synths and the eerie clack of electro-castanets. First-time feature director Olly Blackburn, a music-video veteran, keeps the action compact — an escape is attempted, then foiled; one of the guys brings out a shark gun; one of the girls discovers a novel use for a signal flare. This being an unabashed genre picture (shot in two weeks, for less than $1 million), the ending is never much in doubt. Getting to it, however, involves a slightly better-than-usual assortment of cheap, harrowing thrills.

Don’t miss Kurt Loder’s reviews of “Inkheart” and “The Lodger,” also new in theaters this week.

Check out everything we’ve got on “Donkey Punch.”

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