You might not be too surprised to see a Robin darting about in leafy Mill Hill. But the sight of Batman speeding along The Ridgeway in his Batmobile certainly would be rather shocking.

The caped crusader could be moving from Gotham City to the Green Belt after the National Institute for Medical Research (NIMR) emerged as a possible setting for the forthcoming blockbuster Batman: Intimidation.

Director Christopher Nolan visited the NIMR, which dominates the skyline of Mill Hill, on Thursday last week with two members of his production team.

He is believed to be interested in using the site in the US$135million film, which will be shot in London and feature American Psycho star Christian Bale as Batman and Michael Caine as his trusty butler.

London-born Nolan, 33, famous for his films Memento and Insomnia, is expected to make a return visit sometime this week.

"We had the director Christopher Nolan here and he just walked around the outside of the building," said an NIMR source. "They just turned up unannounced and said: 'Could we have a look around?' "They didn't tell us what the film was but we found out because someone mentioned that Michael Caine was in it and someone recognised Christopher Nolan."

The NIMR, which was completed in 1950, is world-famous for its research into diseases like influenza, malaria and tuberculosis. The building is described by the architecture bible Pevsner rather insultingly as a 'bulky brown brick colossus'.

"It is an extremely unusual building, particularly the design," said the NIMR source. "It is quite austere and I suppose that suits a certain genre of film. It's got that 1920's feel about it and people either like it a lot or hate it."