I saw my friend Sean Langan last night (pictured here enjoying a drink with John Le Carre at a wedding in France last year). He flew back into London yesterday, having been held captive for 12 weeks in the Tribal Areas that divide Pakistan from Afghanistan. Everyone who knew about his incarceration agreed to keep it out of the media until he was safe, reasoning that if the story became public the stakes would be raised and that might delay his release. Consequently, there has been a news blackout until now, but you can read about his ordeal in today's Times, today's Guardian and today's Independent.

He arrived in Afghanistan in February, hoping to interview some senior Taliban commanders for a documentary he was making for Channel 4. He knows the region well, having made several documentaries about the Taliban for both the BBC and Channel 4. Indeed, he made two documentaries for Dispatches last year, the first of which was nominated for a Bafta and won a Rory Peck Award and the second of which was nominated for an RTS Award and won a Banff Award. He risked his life to make those documentaries and his friends and family, as well as his colleagues at Channel 4, were naturally very concerned about him from the moment he set foot in the region.

His last contact with his family was on March 24 when he called his ex-wife and spoke to his two young sons. He told her he was going to enter the notoriously dangerous Federally Administered Tribal Areas of Pakistan the following day, having arranged to interview a senior Taliban commander.

After a couple of weeks had elapsed, and Sean still hadn't been back in touch, everyone began to worry. The hope was that he was simply unable to use his satellite phone in the area for security reasons.

It didn't become clear that he'd been kidnapped until a member of the group holding him made contact with a family member of Sean's Afghan interpreter on May 17th or thereabouts. (His interpreter was imprisoned alongside him.) It soon became clear that Sean had been held captive from almost the first day he set foot in the Tribal Areas, having been betrayed by the people who had arranged his trip and guaranteed his security.

After the phone call, a team of experts was assembled who then entered into a protracted negotiation to secure Sean's release. He was eventually set free on Saturday, having been imprisoned for approximately 12 weeks. He would have been released earlier, but he refused to leave without his interpreter. An Italian journalist kidnapped in the region last year was released, but his interpreter, Ajmal Naqshbandi, remained behind and was subsequently murdered. Sean didn't want the same thing to happen to his interpreter.

I'm happy to report that Sean seems bloody but unbowed by the experience. For most of the time he was locked up in a 6ft by 8ft room and at one point was so convinced he'd be killed that he kept a candle burning at night so he would be able to see the face of the man who slit his throat. Physically, he had a very tough time, losing three stone in weight and having to contend with bouts of malaria and dysentery. He has lost two teeth, and broken four. Yet in spite of this, his morale remained high and he kept his wits about him throughout. As anyone who has ever met Sean can tell you, he is an extraordinarily charming and charismatic man, able to form a close bond with anyone within seconds of meeting them, no matter who they are. He told me last night that he used every last ounce of charm to befriend his kidnappers, knowing from having made a documentary about some British hostages who were killed in Kashmir that his fate could turn on whether his captors took a liking to him or not. I suspect that this, in the end, is what saved his life. When he was released, several members of the group holding him urged him to get in touch should he ever return to the region, almost as if he was parting company with a group of old friends instead of a gang of murderous cutthroats. "It was surreal," he said.

Incredibly, Sean was allowed to keep a journal during his ordeal and yesterday he showed me 17 dog-eared notebooks, all brimming with his spidery handwriting. I have to confess, I envied him at that point. Sean is a talented writer as well as a gifted documentary maker and to live through an experience like this, and to have emerged with 17 notebooks, is any writer's dream. I can't wait to read what he has to say about it.

Not surprisingly, much of what Sean had to say yesterday was uproariously funny. In a typically English way, one of the things that kept him going was the thought of all the funny stories he'd have to tell if he survived and over dinner with his family and friends last night he had us all rolling on the floor with laughter. Any normal person would be a gibbering wreck after going through an experience like this, but not Sean. He's the bravest person I know.