This horror is pretty crass and generic, yet there is occasionally a wacky gonzo energy to this film by director Mike P Nelson, the seventh movie in the Wrong Turn slasher franchise, which began back in 2003 in the classic 1970s style of The Hills Have Eyes. This is also a reboot or summation in that it is called, simply, Wrong Turn, like the first one, without the number seven.

Charlotte Vega plays Jen, a fresh-faced twentysomething hiking the Appalachian trail with a group of her friends. After rashly deciding to go off the official path, into the dense woodland, in search of a “civil war fort” (an ominous destination if ever there was one), they are gruesomely set upon by sinister hillbillies and mountain men dressed in weird animal furs and skulls like Trumpites invading the Capitol. Jen’s earnest dad, Scott (Matthew Modine), comes looking for her, only to discover something horrifying about who these mountain folk actually are and the strange alternative society they have built in secret deep in the forest wilderness for a century or more.

This film really is horribly violent, with people getting their skulls crushed, heads bashed in, ribcages collapsed and generally mutilated in all sorts of loathsome ways. It is by-the-numbers stuff, but the film starts to up its game when we find ourselves in the weird proto-postapocalyptic society in the hills that has stayed the same since the 19th century (but which, apparently, was founded on non-racial lines in opposition to the Confederacy and the Union). Jen gets a bit of a story arc that goes a little beyond the survivalist pieties of the Final Girl. It’s a bit silly and queasy, but the narrative motor keeps humming.

• Wrong Turn is on digital platforms from 26 February.