Keri Collins, 31, who lives near Chepstow, Monmouthshire, is flying out to Los Angeles this month. Actor, director and producer Branagh has been mentoring Collins as part of a scheme for emerging UK talent. Branagh's film version of the Marvel comic book features stars such as Sir Anthony Hopkins and Natalie Portman.

Collins, who will "work shadow" Branagh for a week, said the opportunity was "fantastic". "Hopefully, as my career develops, I'll end up working on big films but it's such a big film - you can go through your entire career and never work on such a big film," he said.

'Thor', which first appeared in Marvel's comics in 1962, is due to be released next year. Filming started last month. In the film, the warrior Thor is banished to Earth after reigniting an ancient war. Once there, he comes to humanity's aid when invaders arrive from his home land of Asgard.

"I'm going to the studio set in Los Angeles which will be my first time on a proper film sound stage," said Collins. "It's amazing he's amenable to me doing it really - for me being there for a week. When I asked for Ken as my mentor, I had no idea he was doing Thor or doing anything that big."

Branagh is well known for big-screen Shakespeare adaptations such as 'Hamlet', 'Henry V' and 'Much Ado About Nothing'. His other work includes TV lead roles in 'Shackleton', about the Polar explorer, and the BBC One series about the Swedish detective Kurt Wallander.

Collins, who studied at the International Film School Wales in Newport, linked up with Branagh when he was one of 25 people chosen in 2008 for the Guiding Lights mentoring scheme.

He initially met Branagh on the set of Chekhov's 'Ivanov' in London's West End after being invited to see the play and meet the actor to discuss how the mentoring would work. Although the formal mentoring period is over, Branagh agreed to continue helping Collins on an informal basis.

Collins is also busy pursuing his own film career, having written a short film for BBC Wales entitled 'Control-Alt-Delete' and getting shortlisted for the UK Film Council's Digital Shorts scheme with his film 'Colwmbo'.