All films made about Lee these days require approval from Lee's estate or his siblings, says Brian Chung Wai-hung, chief executive of the Hong Kong, Kowloon and New Territories Motion Picture Industry Association.

The actor's siblings control the rights to his story before 1959 (when Lee headed to San Francisco), while the Bruce Lee estate, headed by his widow Linda Lee Cadwell and daughter Shannon, has a say over any depiction of Lee after he attained success in Hollywood in the 1960s.

In My Brother, Lee (played by Echoes of the Rainbow star Aarif Lee) is depicted as an upstanding youngster who goes up against racist colonialists and drug-peddling gangsters, and a shy romantic suffering unrequited love.

Lee's teenage years reveal as much about him as the hit films in the 1960s and '70s, says Hong Kong Film Archive programmer Sam Ho Sze-wing.

'You can see his physical abilities in those early films,' he says, referring to the Hong Kong movies which Lee appeared in before he left for the US.

'These films don't involve fight scenes but you can already see how he's very much in control of his body from the cha-cha scenes he did in The Orphan.'

Bruce Lee, My Brother features several re-enactments of Lee's time on movie sets of Thunderstorm and The Orphan, where the young Lee showed a versatility rarely displayed in his fighter persona in the 1970s.

'He's a very good actor with a great emotional range,' Ho says. 'Perhaps it's because he was Lee Hoi-chuen's son, he grew up around film sets.'

The screen persona in My Brother fits with the hyperactive delinquent that Lee played as a child actor in the '50s. But a more realistic view of the teenage Bruce might be gleaned from an earlier production.

What You Gonna Do, Sai Fung?, an hour-long, self-financed film about Lee's last day here before he left in 1959, predates Bruce Lee, My Brother by a decade and was made on a miniscule budget of HK$180,000. However, in depicting Lee as a confused teenager before he became a much-revered superstar, it was ahead of its time.

Made by actor-director Stephen Au Kam-tong, the 1999 film broke away from the mainstream views which depicted Lee as an almost superhuman figure. Instead, Au portrayed the adolescent in everyday situations: having to back down after getting into a scuffle with neighbourhood toughs, catching up with friends at a cha chaan teng and saying goodbye to his martial arts teacher Ip Man.

Au says it was important for him to show Lee as a human being, rather than the muscular fighter with the 'contorted face and strange screams' which had become his trademark.

'It's just one of the ways he expressed himself,' says Au. 'It's sad, however, that most people don't look beyond that and understand more about his views on martial arts.'

That's why he and fellow fan, designer Eric So, have been using new ways to rally a younger generation to the star: he makes films and So designs trendy figurines and clothing.

For Lee's 70th birthday, the pair decided to update their film tribute, re-editing the clips and correcting the fading colours. Their greatest challenge was replacing the original ending, a hybrid of live action and animation that is decidedly passe in the age of 3-D productions.

'In 1999, audiences gasped when they saw this segment where Bruce Lee appears with this animated head over an actor's body,' says Au. 'If people saw it now, they'd be rolling around in laughter.'

To bring out Lee's views on life and martial arts, he shot a two-minute segment using an episode from his time in Los Angeles in 1970, which shows Lee writing a letter of encouragement to a friend.

The letter is being written by an apprehensive Lee, then nursing a crippling injury, as he prepares to return to Hong Kong after enduring a string of frustrations in the US. For all his efforts, Lee only wound up with supporting roles in the television series The Green Hornet (in which he played Van Williams' Japanese sidekick Kato) and the film Marlowe (where he played a hitman who fails to kill the titular detective played by James Garner).

'It's a pretty gloomy scene,' Au says. 'People always see the upside of Bruce Lee's life - but it wasn't plain sailing. Beyond his films, he's just a normal human being - a street punk, a struggling actor.'

They hope to take the new version of What You Gonna Do on a tour of local universities and secondary schools, and Au is already planning another Lee-related film. Like What You Gonna Do, it will revolve around a single day - July 20, 1973, when Lee died in Hong Kong at the age of 32.

'You might say it's got nothing to do with him,' Au says. 'But it's about these individuals whose lives were changed by his death.'

Bruce Lee, My Brother hits the cinemas today