The documentary-maker Adam Curtis has said that when he's at work on an idea, he spends days sitting in a darkened room watching old news clips, trying to make connections. As a technique, it has served him well. For The Power of Nightmares - in which he posited that al-Qaeda is essentially a creation of western governments who use fear to connect with their populations - he dug up footage of Donald Rumsfeld saying the same things of the USSR as he later did of Osama Bin Laden, an echo that had liberals rubbing their hands in glee.
However, his new series, The Trap: what happened to our dream of freedom (Sunday, BBC2), is so jumpy and feverish, you do wonder if his mole-like antics might finally have taken their toll. In using just about all that has happened in science and economics in the past 50 years to boost a single, spooky argument - we are in a cage! - Curtis is now scarily close to becoming what the neo-cons always said he was: a conspiracy theorist. He needs to get out more.
His new series suggests that the paranoid ideas born of the cold war, inspired by game theory, and pushed by the muscular young analysts of the Rand Corporation, have come to influence political thought pretty much ever since: in Curtis's hands, in fact, this paranoia explains everything from Prozac, to Labour's devotion to "targets", to the invasion of Iraq. Part one (of three) was called: "Fuck you, buddy," a reference to a game invented by the mathematician John Nash, the father of game theory, which was supposed to demonstrate that human beings are isolated, suspicious, selfish units, keener on betrayal than co-operation. This theory, in Curtis's hands, chimed with that of Friedrich von Hayek, who thought altruism had no place in any economic model. You can see where this is going. If self-interest is the best deterrent and incentive there is, who needs the state to referee our activities?
Hmm. So far, so good. I tried not to worry too much about the fact that John Nash is a paranoid schizophrenic and, thus, somewhat unreliable on the matter of who is after whom (and, sure enough, he now thinks his model was too savage). Curtis had conjured some amazing stuff: his interview with Nash was surpassed only by the creepy film he'd found of the psychiatrist R D Laing, looking sinister in a polo neck as he expounded his hunch that even those who care for one another are more interested in "strategising" than simple acts of love. But still, Curtis's rhetorical leaps were unsettlingly giant. One minute he was telling you how psychiatrists developed a way of diagnosing mental disorders based on computerised questionnaires, the next, we were in Downing Street, where Margaret Thatcher was getting excited about the American economist James Buchanan. It was disorientating - to put it mildly - to find that, in the blinking of an eye, the skull-like R D Laing had morphed into Antony Jay, the creator of Yes Minister.
The longer the film went on, the more it became obvious that its huge, sweeping argument didn't add up. Curtis often gets cause and effect mixed up. Worse, he links everything sinisterly to everything else, in an often quite batty way. The visual rhetoric - his use of silent movies, his Fritz Lang-style shots of drones in cubicles - is mesmerising. But it is also corrupting. Give yourself over to these images, and to Curtis's calming narrative voice, and there is the danger that you forget that his argument is one among many; that this stuff is provocative, but not necessarily true. Have we really, as he suggests, sent ourselves mad, by rushing to embrace terms such as obsessive-compulsive disorder? (How he gets from game theory to OCD is just too labyrinthine a journey to explain here.) Of course not. Nor is Prozac, however much it may be over-prescribed, enslaving entire western nations. I'm glad Curtis exists, and that the BBC allows him to get on with his strange, nightmarish projects. It's never a bad thing to be made to think. But in his own stylish way, he's as much of a propaganda merchant as the ideologists he sets out to unmask.
Pick of the week
Sunday 18 March, 9pm, ITV1
Billie Piper stars as mousy Fanny Price, which is quite odd.
Life on Mars
Tuesday 20 March, 9pm, BBC1
The long-awaited Camberwick Green episode.
The Trial of Saddam Hussein
Wednesday 21 March, 11.25pm, BBC2
Account of the infamous trial.