Most cinematic approaches to Aleister Crowley have been indir­ect, presenting ‘Black Magician’ figures inspired by the ‘Wickedest Man in the World’ in a number of horror movies. The new British film Chemical Wedding, by contrast, engages directly with the man and the myth, asking what might happen if the ‘Great Beast’ were to be reborn and unleashed on the unsuspecting 21st century.

The film begins with a flashback to 1947 and Crowley’s death in Hastings, seemingly brought about by rocket scientist and Thelemite Jack Parsons’s attempt to perform the Babalon Working in far-off Pasadena – a plot point that not only resonates later in the film but also provides a springboard for its theme of the confluence of science and magick.

Fast-forward to Cambridge in the year 2000, where scientists are experimenting with a state-of-the-art Virtual Reality suit brought over from Cal Tech and a super-computer called Z93, whose programmer is an obsess­ive Crowleyite. When his friend Professor Haddo (Simon Callow; the name is pinched from Somerset Maugham’s Crowley-inspired novel The Magician), an eccentric English professor with a speech impediment and a secret life as a Mason, tries on the VR suit, things go badly wrong. At the next morning’s Shakespeare lecture, Haddo appears with a shaven head, declares that the bard was an occultist and urinates over his students. It’s clear that the professor is not quite himself – in fact, he’s been ‘possessed’ by Crowley, who plans to stay in this new body.

And it’s really from this point that things go downhill fast, with the film jettisoning its sense of humour and turning into a standard contest between good and evil in which a student journalist and a visiting American scientist try to prevent the Beast from completing the occult ritual that will allow him to remain on Earth and continue doing bad things.

Co-written by Iron Maiden’s Bruce Dickinson and director Julian Doyle, the film lurches from black comedy to po-faced, heavy metal absurdity: at times it’s rather as if Spinal Tap had decide to make their own version of The Devil Rides Out. The script is the main problem – confusing, repetitive and unforgivably silly, its dialogue larded with indigestible chunks of Shakespeare (as if this would make us take the whole thing seriously) and its situations becoming ever more hackneyed.

Despite its shortcomings – and they are legion – the film does have a lot of fun with the whole Crowley mythos, and playing ‘spot the reference’ (characters have names like ‘Victor’, ‘Leah’, ‘Mathers’ and ‘Symonds’) may keep viewers amused. In the end, it’s a sporadically interesting, fatally flawed addition to cinematic Crowleyana, and one that will probably appeal to quite a few of the Great Beast’s fans – at least those of them who revel in stories of his legendary bad behaviour; modern-day Thelemites who actually take this stuff seriously will no doubt be deeply offended.