'Nanny McPhee Returns' Star Used Snail Mail To Woo A-Listers

'I always send the script with a nice letter,' Emma Thompson says of casting Ralph Fiennes, Ewan McGregor.

Despite her less than comely appearance, the magic-wielding Nanny McPhee delighted audiences enough in 2005 for her to make a second trip to theaters in this week's "Nanny McPhee Returns." When MTV News caught up with the film's star and screenwriter, Emma Thompson, she told us that taking on dual roles is "hugely satisfying." She also had no complaints about the hours spent in the makeup chair, calling them a reward for having spent a "few years writing the story."

The story is kid-centric and full of fantasy-like surprises — piglets that perform a synchronized swimming routine in a pond, a baby elephant and goat that spend a night in children's beds — and boasts appearances by esteemed actors Ralph Fiennes and Ewan McGregor. When we asked Thompson how she managed to snag the two busy men for the film, the Oscar-winner said it all came down to a simple exchange of favors.

"Well, you know, just one or two quite simple sexual favors, and that was it," Thompson joked. "Not much [effort was required], really. Not bad, they were very generous," she laughed, adding, "I should be so lucky, quite frankly."

The real story is that Thompson used good old-fashioned snail mail.

"I always send the script with a nice letter, 'Look, you know, if you fancy it, would you?' And they both said yes immediately," Thompson explained. "I'm very grateful to them because they're both wonderful."

Thompson also dished about how both she and Fiennes had appeared in at least one

"Harry Potter" film, a feat that seemed to have been accomplished by every working actor in the U.K. Thompson plays kooky sometimes-psychic Professor Trelawney.

"Absolutely everyone in equity has been in it," she joked of the franchise's lengthy cast list. "Including all my family, practically, my sister just finished. I don't know what the name of her character is; she's got a major role in this last one."

Check out everything we've got on "Nanny McPhee Returns."

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