A serial killer gets very upset about a Black Friday sale in a throwback slasher pic from the ‘Hostel’ director.

I’ve heard of long-lead movie trailers, but this is ridiculous.

The film set in (where else?) Plymouth, Massachusetts, does begin spectacularly, with an elaborate, expertly staged sequence depicting a riot at a big box store named Right Mart (any resemblance to Walmart is strictly coincidental, presumably) on Thanksgiving night, the start of its Black Friday sale. An only slightly exaggerated rendition of the sort of violent mayhem that has actually occurred in various places, the tragic event results in several gruesome deaths, including one involving one of the more recognizable cast members. Needless to say, the harrowing footage captured on a cell phone camera quickly goes viral.

Investigating the killings is McDreamy, excuse me, Sheriff Newland (played by Patrick Dempsey, fresh off his coronation as People’s “Sexiest Man Alive,” which I’m sure is a total coincidence). The hard-working sheriff has his work literally cut out for him as John Carver lives up to his name by chopping and dicing — and in one case cooking someone alive like a Thanksgiving turkey — his way through the community, including several of its particularly attractive young people. The killings, delivered with the sort of practical effects that you can imagine its creators gleefully devising, are quite imaginative; there’s one involving a sexy cheerleader being knifed to death on a trampoline and another involving a parade driver getting his head impaled by the wooden bowsprit of a Mayflower float (loved the detail of the nose hanging dejectedly off to one side as a result).

“No one appreciates subtlety anymore,” one of the characters ironically complains, and the film is a case in point. There’s exactly nothing subtle about this effort, including the heavy New England accents sported by many of the actors, which result in such amusing exclamations as “Oh, my Gawd!”

The screenplay by Jeff Rendell, who devised the story along with Roth, features welcome doses of the sort of self-aware humor that reassure us that the film is not to be taken too seriously, although without lapsing too heavily into the sort of meta territory the Scream films have now done to death. There are also clever visual touches throughout, as when Jessica attempts to hide from the killer by blending in with a series of mannequin heads sporting wigs.