Television and Radio: The new Potter: predictably unpredictable

You know where you are with a Dennis Potter script: lost, but lost in a landscape that is strangely familiar. In Midnight Movie (BBC 2) there were the old signposts - the obsessions of nostalgia and desire, the shucking off of bourgeois restraint , the script that folds in upon itself, and dialogue that decelerates to admire its own authenticity in the mirror - though, as usual, they were all pointing in different directions.

This was the last of his scripts that Potter saw filmed, and to the trick of not knowing where you are within one drama he added another twist. With Louise Germaine reprising her role as a pneumatic peroxide scrubber for whom all sexual partners are"dirty little sods", Midnight Movie quoted liberally from the text of Lipstick on Your Collar.

With anyone else this would go down as a failure of imagination. With Potter, who could no more have delivered himself of a plot that goes from A to C via B than he would have invited Rupert Murdoch over for tea and crumpet, it can't be so simply dismissed. When you hear an echo in Potter's work, it is safe to assume it's intentional. What the intention was here, though, is harder to divine.

It is also impossible to tell whether Germaine, here doing another pouting, often naked barbie-doll, is in fact a limited actress, or whether it is the narrowness of Potter's stereotyping that makes her look like one. You can almost imagine her in interviews referring to Potter himself as a "randy little devil". Whatever, she at least plays a limited actress called Amber, and just to confuse the issue, she also plays her character Amber's mother in the midnight movie within Midnight Movie.

Amber and her sugar-daddy Boyce, a philistine Hollywood producer played with his usual barrel-chested gusto by Brian Dennehy, rent a Jacobean country pile while he's shooting at Shepperton. Henry Harris, the local solicitor who organises their affairs, tells them that the house was used as the set for Smoke Rings, a Sixties horror flick in which Amber's mother, Mandy Mason, played a psychotic blonde mankiller. In real life, Mandy subsequently died in a car crash from which the unidentified driver (who turns out to be Boyce) got away.

This wouldn't be Potter if the real and the reel didn't intertwine. Harris - a mixture of the stolid and the sinister, perfectly meshed in the person of Jim Carter - doesn't "get involved with people". But that's not to stop him getting involved with characters: he knows Smoke Rings by heart and starts to act it out with the daughter of its star. Amber plays her part by bedding then bumping off a scriptwriter and a roofer, but because she's schizophrenic she knows nothing about it. (The circumstances ofthe scriptwriter's death are particularly suggestive. A dog unearths the corpse, bites off its member and buries it elsewhere: in Potter's scripts the scriptwriter is always found guilty.)

And so it goes on, in predictably unpredictable fashion, towards resolution. The post-coital killings all seem to be happening in the script inside Harris's head - but then, as in The Singing Detective or Blackeyes, for Potter that is as valid a place asany. When Harris tells Amber she can have a part in his movie, it's not the big opportunity she's been waiting for.

The director, Renny Rye, has fun with the grammar of Hammer Horror, which dictates that no film is complete without a cracking thunderstorm. It is entirely apt that Potter should not only open but also close with one, because boiled down to its essence the plot of Midnight Movie, and the plot of Potter's career, are the same: lightning sometimes strikes in the same place twice.