Taken globally, Taiwanese slasher Invitation Only is just another film following in the footsteps of the "torture porn" vogue, as exemplified by Saw, Hostel and a bunch of other films that delight in slow, nearly affectionate scenes of human mutilation. Invitation Only has the signifiers that one expects – defenseless victims, severed limbs, buckets of blood, unflinching gore, gratuitous nudity – and qualifies as a perfectly serviceable entry in this notorious genre. Unfortunately, the film also has some of the genre's negative signifiers, like bad dialogue, bad acting, and a premise that's less chilling than it is familiar, especially since this nihilistic genre has become so firmly established as a mainstream guilty pleasure.

The big caveat: this is Taiwan's first attempt at such a film, and they gleefully do their best to deliver the blood, gore, sadism and other grindhouse pleasures that genre fans require. Director and co-editor Kevin Ko and his Invitation Only crew seem to be having a ball, and never pretend that this exercise in exploitation is anything greater than that. Handsome Bryant Chang (Eternal Summer) stars as Wade, a lower-class schlub who works for Mr. Yang (TV drama actor Jerry Huang), rich and powerful CEO of the Weida Group. Wade accidentally spies Mr. Yang having sex with supermodel Dana (Eurasian AV star Maria Ozawa), but instead of getting canned he receives a minor reward. Mr. Yang sends Wade to an exclusive party in his stead, where he can carouse and network on the company dime.

It's all a bait and switch, of course. Wade is asked to write down his greatest fantasy, and he wishes for an expensive sports car, which he's given at the end of a hedonistic evening that includes gambling, dancing, and even a roll in the sheets with the suddenly accommodating Dana. Other "newcomers" to this exclusive club are also given some nice parting gifts – but before anyone can actually leave with the object of their heart's desire, they're separated from one another and subjected to stalking and slashing from a masked assailant, with an option on mutilation if they stand still long enough. There's a secret behind all of this evil, but it's only novel if you've never seen similar films. Basically, there's a bunch of people who don't like a bunch of other people, so killing them cruelly seems a fine option. Cue torture and dismemberment.

Production-wise, Invitation Only is a low-budget affair; the film was shot on high-def and the art direction is only a step up from "converted warehouse". Still, the gore effects are well executed and the filmmakers even went the extra distance, getting organic insects for an icky sequence where Bryant Chang squeezes the entrails out of a poor cockroach. People get beheaded, stabbed, scissored, stapled and more in this ninety-minute gore-a-thon, and while it's not as over-the-top as its Hollywood counterparts, the film does provide that tension-through-torture fix. The POV handheld camera effectively builds towards the bloody payoffs, and the attempts at social commentary are entertaining if not incisive. There are also some gross laughs and a gratuitous Maria Ozawa sex scene to charm the masses – that is, if her dozens of AV films have yet to provide fans with their bump-and-grind Ozawa fix.

Unintentional humor value is high, too. The script is sometimes hilariously awful, with characters saying things like "Did you hear that?" after a plainly audible gunshot or "Is that a door?" when standing only ten feet from an exit. Once everyone realizes they're in danger, they – what else – split up, and English-language dialogue is delivered deadpan to uproarious effect. There are some missed opportunities: one of the victims, lovely and sympathetic bank employee Hitomi (Julianne), expresses that her greatest fantasy is to get back the lost teddy bear from her childhood. Unfortunately, the filmmakers never show us that moment - which is a shame because it could have raised the film an extra notch in the camp exploitation canon. Just think: wouldn't it be a hoot if she got back her childhood teddy only to have it eject spikes and slice off her fingers? Given the film's ending, there always a chance we might see that in Invitation Only 2. (Kozo, 2009)