One thing to be aware of when watching any of Ken Russell’s films is that you will spend at least three quarters of the running time saying to yourself, ‘What THE HELL am I watching.’

Mr Russell’s The Lair of the White Worm (1988) is so bizarre that… well, let’s just take a look at the notes I made the last time I watched it:

‘How do you spot a snake vampire cultist lady? She’ll be playing snakes and ladders. In thigh high boots.’

‘Gratuitous historically inaccurate nun torture.’

‘Where IS Peter Capaldi keeping that mongoose?’

Very loosely based on Bram Stoker’s original story, the film takes an olde worlde horror setup and adds a fantastic lady monster (Lady Sylvia Marsh, as played by Amanda Donohoe – a saucy aristocratic predator who thinks white three corner hats are casual wear) and a high pile of hallucinatory WTF.

(Unfortunately, Bram Stoker’s The Lair of the White Worm is not a great read. It’s got potential – Lovecraftian horrors stirring beneath the English countryside – but it’s clunky as hell. And contains so much sexism and racism that it reads like an unsubtle parody of a Victorian horror tale.)

Peter Capaldi plays Angus, an archaeology student who finds the skull of some kind of monster in the garden of a B&B in Derbyshire. The B&B is run by two sisters – Eve and Mary (Catherine Oxenberg and Sammi Davis. Note the unsubtle choice of names) whose mother has disappeared in mysterious circumstances.

Then Lord D’Ampton (Hugh Grant) invites them to his ancestral hall for an 80s folk/rock party, where he re-enacts the legendary tale of an ancestor of his, who killed a giant worm (guess what colour it was.) that was terrorising the village some centuries previously.

(The beast that his ancestor had the squabble with was the D’Ampton Worm. As in the Lambton Worm. Both Stoker’s and Russell’s version of ‘White Worm’ take place in Derbyshire and not Durham. There were a lot of worm monsters about in the olden days, apparently.)

This gets Angus wondering – could his new-found skull have something to do with the one in the tale? Lord D’Ampton is foppishly sceptical. And then Lady Sylvia slinks into view. And spits venom on a crucifix. I haven’t seen Downton Abbey for ages, but I’m pretty sure that her TV namesake is not in the habit of doing such things.

What follows is an unsettling campfest. Lady Sylvia does some horrible things (that poor boy scout) but she’s also horribly fascinating. I don’t know if she was meant to be a satire on the ‘sexy sex ladies who are EVIIILL’ trope or an unsubtle parody of 80s decadence (see Kate Beaton’s marvellous Dracula cartoon for a nice pisstake of how this trope came up in Stoker’s most famous tale). But either way Ms Donohue looks to be really enjoying herself.

Eve and Mary are sketchily drawn characters – it transpires that Eve is a virgin, which makes her sacrifice fodder for the great big worm beast living under Sylvia’s mansion (paging Doctor Freud). Lord D’Ampton has some rude dreams and tries to fix things with his super posh man skillz. Eventually, Angus has to face vamped up Sylvia alone. Yep, Peter Capaldi is the Final Girl.

He does a bit of snake charming with a kilt and a set of bagpipes. And a mongoose. If anyone’s concerned that Doctor Who-loving kids might come across Malcolm Tucker’s epic swears by accident online, wait until they get a load of this.

Lair of the White Worm is basically awesome trash. Or it’s trash cinema French kissing arthouse cinema down a dingy alleyway. And sometimes that’s what you want.

• Emily McQuade lives in North London. She enjoys finding weird old films on YouTube and watching other weird old films at the BFI. When not thinking about films, she enjoys books, gigs and making up elaborate conspiracy theories involving squirrels. She can also be found on Twitter: @missmcq.