'We found the people of North Korea extremely welcoming,' says Gordon. 'They were proud that English people still remembered their heroes. The players remain our close friends. On every occasion we return to North Korea we meet up with the players for a meal.'

He has made another two North Korea documentaries, A State of Mind, which features schoolgirl gymnasts at the country's annual Mass Games, and Crossing the Line, about James Dresnok, an American GI who defected to the north in the 1960s.

Gordon's fascination with the team began when his father gave him a copy of Goal! World Cup 1966. Whereas his family and friends watched the film repeatedly to savour England's sole triumph in the history of the tournament, Gordon says he was more impressed by the North Koreans. 'I could name all the players from the 1966 team, all the scorers, even the minutes of their goals. This is a story that's legendary in England, and I'd grown up hearing about their exploits. But no one knew what happened to them after they returned home. That's what inspired me to make the film.'

Gordon admits that he 'knew nothing of the country itself [and] had no preconceptions about North Korea' when he began planning for The Game of Their Lives. He says the main challenge wasn't getting permission to film in the country (he insists that the authorities, which provided guides and translators at all times, didn't interfere with his work), but gaining the confidence of broadcasters back in Britain.

'I had a whole file of rejection letters from people who didn't think we had a story,' he says. 'The BBC were keen, but wanted to make sure we could deliver the material. Fortunately, once we left North Korea with some stunning footage, the BBC were on the phone and we had a commission.'

The enthusiasm is no surprise, given the poignant material on offer in The Game of Their Lives, which screens on Thursday and Saturday as part of Games of Asia, the Asia Society's sports-related Summer Film Series (which includes Iqbal, about a hearing- and vocally impaired cricketer, and South Korea's boxing movie Crying Fist).

Whereas soccer aficionados may lap up the archive footage with delight, including the Park Doo-ik goal that sent Italy crashing out of the tournament, it's the fresh interviews with the team members that stir emotions, as they recall their endeavours and their fond memories of how the people in Middlesbrough - the city in which the Koreans were based in 1966 - took them to their hearts.

'The first words they said was, 'How is the mayor of Middlesbrough?',' says Gordon. 'I think that says it all about the powers of their memories. They love England and the people here.' The tradition of championing the underdog in Britain's industrial northeast made the North Koreans darlings to the local population. One report said 3,000 fans went to Liverpool to cheer on the team in their match against Portugal.

During that evening of revelry in May 2002, one of the North Korean veterans suggested that it would be great if the team could revisit Middlesbrough. Which was what Gordon and producer Nick Bonner tried to organise during the next few months, as they battled bureaucracies in London and Pyongyang to get the surviving members of the 1966 squad to Britain.

Incredibly, the trip - which Gordon dubbed 'the North Korean World Cup Squad Tour 2002' - was finally arranged in October that year. The soccer players visited the site of Ayresome Park - the stadium in which they defeated Italy has been replaced by a housing estate - and were visibly shaken when they were treated as returning heroes by both admirers from 1966 and younger generations.

'I think they were over-whelmed by the reaction - especially when six-year-olds were seeking them out to get their autographs because their grandfathers told them to,' says Gordon. 'What I've found is that, through football, and also sports, in general, people can break down barriers that were thought insurmountable.'