Last Night's Viewing: Captive - the Sex Slave Girl: True Stories, Channel 4 Young Apprentice, BBC1

The saddest line in Captive – the Sex Slave Girl: True Stories came from a former classmate of Tanya Kach. "Honestly?" she confessed, in an apologetic voice. "I didn't know she was missing until she was found."

That told you pretty much everything you needed to know about how Tanya fitted into her world – that and the fact that a missing person's report wasn't filed with the police until four days after she'd failed to come home. Tanya's dad thought she'd run away (she'd been having trouble at home with her step-mother), Tanya's school thought she was skipping class again (as she had done before) and Tanya's classmates didn't even notice she was gone.

In fact, Tanya was living just down the road with the school security guard Thomas Hose, who'd somehow managed to persuade this unhappy, troubled 14-year-old that a run-down clapboard house in the worst area of a rust-belt Pennsylvania town was a fairy castle. "I thought I had met my prince, because he sure acted like it," said Tanya.

Ten years later, she re-appeared, or rather identified herself, having spent several years living an apparently normal life under another name. Tanya's story was that the fairytale had gone bad. She'd spent years living in secret in Hose's bedroom, sexually abused by him and terrorised into compliance.

By her account, his elderly parents, who lived in the same house, never knew that she was in there, and his son, who slept on the floor of the same room, had been pressured into silence. And almost immediately quite a few people suggested that Tanya too "didn't know she was missing until she was found". Captive wasn't a simple tale of heroic survival against the odds. It was a story about suspicion and doubt and the mysteries of human behaviour.

A pretty depressing one too, even if you decided to acquit director Rob Farquhar of the charge of supermarket-tabloid prurience that his title invited. Because it was almost impossible to watch the film without becoming suspicious and untrusting yourself. Was Tanya's father telling the truth when he recalled scouring the neighbourhood night after night looking for his daughter? Or was Tanya right to believe that her disappearance had solved a problem for him and his second wife?

Had Tanya's abuse at the hands of her own mentally disturbed mother twisted her so badly that she would lie about what had happened? Or had it merely made her the perfect victim for a calculating and controlling man? For some people, Tanya is an exemplary chancer, manipulative and deceitful. For others (and herself on this evidence), she's an exemplary victim, bravely witnessing to the dangers of paedophilia.

You simply weren't given enough evidence here to make a firm decision either way. And it didn't exactly help that virtually every interviewee looked as if they'd stepped straight out of a Carl Hiaasen novel, from the jaded local reporter who'd covered the story to the publicity-conscious lawyer who'd defended Tom Hose (he had a replica electric chair in his office).

Even Tanya herself had lines that trembled on the edge of black comedy. "I was on 400 million milk cartons," she said solemnly at one point, as if boasting about her fame. In the end, you were left with one thought: the benefit of the doubt should always go to the 14-year-old, not the creepy guy who thought it was a good idea to keep her as a collectible.

Society does sometimes look the other way though. For weeks now, a leathery-faced old man has kept a whole group of teenagers captive in a luxury house, making them perform humiliating tasks and then berating them if they fail to turn a profit for him. Unfortunately, all those taking part in the Young Apprentice insist they desperately want to stay and will fight like weasels in a sack to make sure they do. Talk about Stockholm syndrome.

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