Poor artists imitate,” we were told more than once on last night's docu-drama The Antiques Rogue Show, which for no good reason mangled Picasso's famous remark that bad artists copy and great ones steal. Now, I would be loath to thrust greatness upon the producers of Saturday night's new sorcery saga Demons, but

they certainly know how to steal with panache. Their hero is a fit London teenager called Luke, who is press-ganged into the coldest of cold wars, “the struggle between human and inhuman”, that is to say non-freak and freak. Luke may bear the surname Rutherford but he is also the last Van Helsing, and that makes him a vampire hunter because as, with chimney sweeps, the profession is hereditary.

Before, however, we could accuse ITV of stealing from Bram Stoker, Demons was accusing Bram Stoker of stealing Luke's name for his novel. “Identity theft,” explained Luke's godfather Rupert Galvin, played by Philip Glenister, here to steal the show from its young lead, the promising Christian Cooke, and to distract us from noticing that Demons had also stolen wholesale from Buffy the Vampire Slayer.

“Other people have a choice. You have a destiny. You are the last Van Helsing. Denial is not an option,” continued Rupert, a sententious American who speaks in bullet points but sometimes tosses them all away in favour of fluent and wide-ranging cliché. “We don't care to name them,” Rupe said of vampires and werewolves. “We just grade them and smite them with extreme prejudice, swiftly and surely like the wrath of God.”

Grade? Why yes. A grade-three demon is a scuttling gremlin who invades Luke's mum's airing cupboard. Grade seven is represented by a gang of hoodies with faces like syphilitic teddy bears. A taller guy with terrible teeth who hawks up his cockroach dinners in owlish pellets reaches grade eight. Grade 12 was awarded to Gladiolus Thrip, a pasty teddy boy with a false nose and breath so bad it will kill you. He is Mackenzie Crook, brought in to steal a scene from Glenister but not allowed time to do more than case the joint. He ended up vaporised, but previews suggest that he will be back. It's his destiny. With no Doctor Who, Robin Hood or Merlin around, I suspect that Demons is ours, too. Grade 13 (Michael) will be pleased, you freaks.

In last night's opening half of Above Suspicion the rookie coplette Anna Travis was accused by her unreconstructed but golden-hearted boss of watching too much television. All she had asked was whether she might wear a wire on her date with a likely serial killer. The accusation was a bit rich since much of the cop telly Anna would have devoured will have been penned by the writer of this very garbage, Lynda La Plante.

Demons has the swagger to carry off its larceny. Above Suspicion just doesn't care and indulges every cop-opera convention going. Travis, played with a slippery estuary accent by Kelly Reilly, turned up at a muddy crime scene in high heels, vomited when shown a corpse and then fainted at its post mortem examination. The male cops eyed her up, the females bitched about her clothes.

I will give credit to the props department for coming up with the most disgusting corpse I've seen and the maggot wrangler for obtaining such energetic performances from them as they crawled over the dead girl's face. But the realism of the gore only highlighted the phoniness of everything else, from the dirty old ex cop in Málaga (played by Corrie's still lamented John Savident), who accused Anna of never having had “a decent f***” to the prime suspect, a smoothy actor the like of which you haven't seen since Ian Ogilivy's turn as The Saint.

“Those eyes, those beautiful eyes, were so empty,” it was explained of his peepers, although they betrayed nothing more than boredom to me. Even the television scenes were incredible: a ridiculous Chicago chat show that cut to audience reaction shots from the Jerry Springer Show and a local news bulletin that ended “And now over to Sally for the weather in the London area”, a pay-off last used by Associated-Redifusion in 1961. La Plante needs to watch more television, not less.

So back to The Antiques Rogue Show, which was the true story of the Greenhalghs, a working-class family who made a living out of forging art works and then selling them to gullible museums. The writer-director Norman Hull got bogged down in his thesis that the importance of “provenance” extended beyond the world of art into society. If the forger had come from Central St Martins, not a Bolton comp, he would be hailed as an artistic genius. “Would anyone buy my unmade bed or dirty knickers?” Shaun Greenhalgh (Jeremy Swift) grumbled to no one in particular.

With the fabulous Peter Vaughan and Liz Smith as his parents, The Antique Rogue Show should have been a real find, but its radio-play wordiness and low production values rendered it a curio rather than a gem.

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