“You fool! I’d rather see you dead than meddling with black magic!”

After a titles sequence involving spooky music, red smoke and vaguely Cabalistic symbols, we're brought straight back into the modern(?) world with the arrival of a plane, greeted by a surprisingly chipper Christopher Lee (the Duc de Richlieu, all-round angry chap and beard model). The plane has been piloted by square jawed type Rex, who wastes no time getting down to the crux of the plot: "Where's Simon?"

Simon has apparently bought a large house (the fiend), and Rex and the Duc get there quickly, crashing a party and meeting up with not only Simon, but Countess Boss-Eyed, evil grey-head Mocata and sex-pot Tanith. "I don't understand," says Tanith. "Surely we're not meant to be more than 13..."

The Duc's eyebrows tell us all we need to know - he is well aware of what's going on here... The pair of them have sworn to protect the younger Simon, but before they can do anything about it they're asked to leave. This obviously happens a lot to the Duc, as he manages to predict it - and before they can be forcibly removed, he legs it up to Simon's new observatory. 

Up in the room the Duc immediately finds a box full of... chickens (possibly the greatest entrance by a chicken in the history of film): "You fool!" he shouts, as he jumps to the only possible conclusion that a basket of chickens offers: "I'd rather see you dead than meddling with black magic!"

And just to explain it completely to Rex the Dunderhead: "Simon here is playing the most dangerous game known to mankind!"

What, asks the audience - chicken racing?

The Duc's immediate answer to this black magic conundrum is to punch Simon out (one of many strangely gratifying punches, slaps and general abuse Mower is to receive during the film) - and drag the unfortunate young fellow away from his own house, giving the Indian butler a kicking for good measure.

Back at the Duc's house Simon is sent to bed with a crucifix, as dim old Rex attempts to come to terms with what's going on: "Hocus pocus... mumbo jumbo... black magic?" and he's none the wiser when the Duc explains that black magic is "a living force that can be tipped at any moment." (Like an evil waiter, then)

Under Mocata's evil power, Simon starts to strangle himself with the crucifix, until the Duc's butler helpfully removes it and allows him to escape. Rex and the Duc follow their young charge back to his house, and of course, the last place they look for him is the observatory. Cue first of the the terrifying not-very-special effects - a big black bloke in a nappy, wreathed in dry ice.

"Don't look at the eyes, Rex!"

Luckily, the Duc still has the crucifix and after defeating the "infernal spirit" he begins to realise Mocata is more powerful than he first thought - and tomorrow night is the Grand Sabbat... oh-oh...

With Simon gone, they must find the girl! Which Rex does after scouring a grand total of 28 hotels in London. She's not happy about being dragged away from the Capital, but lets slip that she hasn't been satanically baptised yet - Tanith is her real name. Rex takes her to the Duc's niece's house, where the family are enjoying tea on the roundabout. But the dolt leaves Tanith in the car with the engine running, and she (not surprisingly) buggers off.

"I must take your car!" Rex tells the man of the house (Richard), "Simon's life depends on it!"

A car chase ensues (a kind of 1920s Ducs Of Hazzard), with tons of CSO, Mocata appearing in Tanith's rear-view mirror, and off-screen stage hands lobbing buckets of water over the drivers.

Despite Mocata eventually making Rex crash, he arrives at Mocata's house in time to hitch a life on the back of a departing car.

At the Sabbat, Simon and Tanith look on as a goat is slaughtered. The so-called satanists gathered around are a nesh lot, and go "ooh..." and turn away as it happens. Nic legs it to a phone and rings the Duc, who answers it in best shouty fashion:

"Hello! Rex! What!"

Back in the woods, there's some absolutely appalling (as in boring and badly acted) debauchery going on (even by Hammer standards - see The Witches for more) - Tanith gets Ribena poured all over her and Simon looks both puzzled and slightly uncomfortable. All this precurses the arrival of the Goat Of Mendes - the Devil Himself, or a bloke with a goat skin on his head, depending on your point of view. He doesn't prove to be particularly scary, however, and is easily dispatched using salt, mercury, that crucifix again, and plenty of car headlamps. Rex wades in with his fists and even manages to belt Mocata, at which point our heroes flee back to Richard's house.

They've not been there long when Mocata arrives (and is let in!), but he leaves when his black magic powers fail at the last minute. "I shall not be back... but something will. Tonight something will come for Simon and the girl..."

Tanith legs it (again) into the garden, and is followed by Rex who ties her up in a stable. That'll stop her high jinks.

Meanwhile, in the house, the scene is set for Hammer's (and horror cinema's) greatest ever set piece, as the Duc makes everyone stand in a chalk circle and the lights start to dim...

Unfortunately, it's the idea of what's going on, rather than the reality, that chills. As the group start bickering and Richard proves himself to be "The Weakest Link" (I always knew that Ann Robinson was the devil), they are assailed by a crap spider and an initially frightening and then crap "angel of death", complete with comical forward-and-backward rearing motion. Luckily, the Duc's on hand to utter some load of old bollocks which alters time and space, but on surveying the aftermath, Tanith is dead ("The angel of death was summoned... it cannot return empty handed") and Richard's little girl has disappeared. Using the power of the hand signals from "Agadoo", the Duc calls on the dead Tanith, who helps them track down the girl (and Simon, who's gone off after her). Mocata plans to sacrifice her, but Tanith has other ideas, after failed fisticuffs from Rex (lame) and Richard (lamer). She says those words again, and everything crashes down around everyone's ears. The group wakes up back in the circle, and all's right with the world. "All these things happened, but now they have not happened," says the Duc, helpfully.

Everyone is still alive - apart from Mocata, who has been taken by the Angel of Death in the place of Tanith (we assume).

The whole exhausting 90 minutes is brought to a finish with this deadpan exchange between Patrick Mower and Christopher Lee:

"Thank God."

"Yes, Simon. He is the one we must thank."

Classic.