Last Night's TV: 9/11: Conspiracy Road Trip/BBC3 Perfect Couples/E4 Happy Endings/E4

Wake-up call for the American dreamers

A few days ago I think I suggested that the only sensible thing to do with 9/11 truthers was to send them to Coventry. My thinking was that if they only had each other to talk to then even they might get bored enough to give up in the end.

In 9/11: Conspiracy Road Trip, the comedian Andrew Maxwell adopted a completely different strategy, taking five confirmed conspiracists on a Dimwits' Holiday to the United States, where he was going to try to introduce them to the alien concepts of probability and critical thinking. He, obviously, was a lot more tactful – openly declaring his own conviction that the Twin Towers had been brought down by al-Qai'da plotters, but declining to indulge in any pre-emptive name-calling. And the resulting programme was actually rather interesting – less for the refutations advanced (which, as we discovered, even novice paranoiacs found it easy to dismiss) than for the opportunity to study at close hand the psychology of the true believers.

Even the off-the-cuff remarks allowed you to identify the distinctive sub-species of the conspiracy nut. There was Charlotte, a nanny in New York at the time of the attacks and clearly a woman who'd been traumatised by that experience: "Something is going on here and I am going to get to the bottom of it," she said, issuing the distinctive call sign of the hero conspiracist, convinced that only personal agency can put the world right again. There was Charlie, a former philosophy student who thought that the World Trade Centre had been brought down by controlled explosion. When Maxwell tried to put counter-arguments, he protested at his willingness to accept the official line: "You're just having this obedient psychology, which is worrying, man," he said, identifying the consensus-phobic, a classic conspiracist type. And then there was Rodney, who put a lot of store in the alleged discovery of "nano-thermite" particles in 9/11 dust. "We're talking about something that very few people know about," he said, nicely illustrating the vanity of privileged knowledge that drives so many conspiracy theories.

Maxwell's method was to introduce the group to experts and witnesses who might resolve some of the issues that troubled them. One of the group was given a flying lesson, to demonstrate that the difficulty of flying a jet into the biggest target in Manhattan might have been exaggerated just a little by the sceptical. A technician set off a pile of thermite on a steel beam to prove that even quite a large quantity wouldn't cut through it. And a demolition expert explained just how much preparatory work would have to have gone into preparing charges to bring down the World Trade Centre. And, rather gratifyingly, not all of those present were entirely impervious to reason. Charlie, who may have skimped his research into the counter-arguments to conspiracy theories, seemed almost startled to discover that there were perfectly rational explanations for phenomena he'd found baffling. Two other members of the party also wavered. But Charlotte and Rodney both displayed the fierce intransigence of die-hard truthers. "I can't just change my mind," said Charlotte, furious at what she saw as a betrayal by her fellow conspiracists. She smiled dismissively as one witness recalled seeing parts of air stewardesses' bodies in the wreckage of the Pentagon (he had a commendation from President Bush on his wall, so to her mind was utterly compromised) and was flatly unmoved when the mother of one of those who died on United 93 tearfully described her son's last telephone call (Charlotte believed it had been faked). Like most conspiracists, Charlotte needed her belief more than the truth, and nothing on earth was going to persuade her to give it up.

E4 launched two acquired American comedies last night – Perfect Couples and Happy Endings – and they are already beginning to blur in my mind, with their sub-Friends perkiness, crash-cut sight gags and wearisomely predictable account of gender relationships. Both exist in that weird alternative universe where busy young professionals have endless amounts of time to sit around on sofas teasing each other and both of them are marked by that melancholy desperation to be likeable that comes from the American commissioning system, which has an attrition rate worse than the Somme. Over the top they go, a rictus grin on their faces, knowing that most of them are going to be dead before the season is over. The only possible thing to say in their favour is that they're more entertaining to watch than Red or Black. But then you can say as much of a tumble-dryer.

t.sutcliffe@independent.co.uk