Horror movie convention gets turned on its bloody head with You’re Next, the latest visit to the home invasion slasher. Though the setup is a familiar one with the proverbial herd of sacrificial lambs converging on an isolated house for a family reunion, it’s what happens throughout the course of the blood-soaked proceedings -- along with a deliciously unexpected tonal shift -- that bring a refreshing take to the spook party.

The Davidson family is gathering to celebrate the anniversary of retired defense contractor Paul (Rob Moran) and his pill-popping wife Aubrey (Barbara Crampton, the legendary scream queen) at their palatial, yet slightly run-down, mansion in upstate New York. In attendance are their four children with significant others in tow. College Professor Crispian (AJ Bowen) brings along Australian girlfriend Erin (Sharni Vinson); obnoxious older brother Drake (Joe Swanberg) is accompanied by Kelly; while spoiled sis Aimee (Amy Seimetz) arrives with aloof filmmaker Tariq (Ti West); and other brother Felix (Nicholas Tucci) introduces his eye-rolling hipster girl Zee (Wendy Glenn).

Dinner has hardly been served before we begin to learn why the family hasn’t gathered in several years. A decades-old sibling rivalry is threatening to derail any hope of reconciliation as brothers Crispian and Drake are soon at each other’s throats. Then, the awkward family conversation becomes disrupted when a noise from outside draws a guest to the window. Moments later, glass shatters, chaos erupts, and guests are scattered throughout the room with one dead and numerous injured.

As the survivors engage in a dangerous game of cat-and-mouse with the masked intruders, we begin to wonder what possessed the bad guys to think of crossbows as efficient killing tools. Sure, a guy taking an arrow to the head is both horrifying and violent for an audience, but bringing our attention to the poor choice of weapons probably isn’t such a good idea.

In fact, hardly any decisions made by director Adam Wingard and screenwriter Simon Barret make much sense, nor do any of the stupid traps our victims walk themselves into. The acting comes across passable at best, and the dialogue seems more often juvenile than not. Then again, that’s part of the campy allure and devilish charm oozing from every frame of You’re Next. Well, that and the gallons of crimson-colored corn syrup. The kill shots are every bit as gruesome and gory as any you’ll ever see, and the underlying pretext -- something about rich people deserving what’s coming to them -– goes refreshingly counter to many of the overtly conservative themes from the ‘80s slasher films, which this one so dearly covets.

Wingard and Barret play it mostly straight to the film’s mid-point, seemingly oblivious to the cloying bits of dialogue like, “We’re all gonna die” or “Why would anybody do this?” Then comes a hellishly wicked tonal shift that not only leads to masterful gems like Zee telling her boyfriend, “I want you to ____ me on this bed next to your dead mom,” but also reveals that the coolest head in the bunch might belong to Erin, who grew up on a survivalist compound in Australia. (SPOILER ALERT) Too bad for the intruders, as she unleashes some kind of primal feminine Home Alone rage that becomes an unstoppable force. Some may remember Vinson as the lively hoofer in 2010’s Step Up 3D. She’s just as energetic here, and this role could prove to be her breakout.

In our current run of films and TV shows featuring evil characters who bask in the anti-hero spotlight, it’s nice to root for the good guys once again, despite a seemingly willful stupidity here that all but predetermines their own demise. There’s also redemptive societal value in knowing that our masked killers learned basic punctuation which is put on bloody display when they inscribe the film’s title in their victim’s blood. Writing “Your Next” would simply be all kinds of wrong.

(Released by Lionsgate and rated “R” for strong bloody violence, language and some sexuality/nudity.)

Review also posted at www.franksreelreviews.com.