Martin Freeman finds it hard to remain positive when he's covered in "snot and mud" on a movie set.

The British actor has been shooting The Hobbit: An Unexpected Journey in New Zealand recently. It's a prequel to The Lord of the Rings trilogy and Martin is portraying hobbit Bilbo Baggins.

The star remains unaffected by being cast in such an iconic role, explaining the hardest part of shooting has been dealing with the environment.

"The hardest thing is staying 'up' and peppy when you're covered in snot or mud, day after day... I'm sure there's more to come," he laughed to Total Film magazine.

"So far, what we've filmed has been more comic than heavy. I keep asking Pete [Jackson, director], 'When are we going heavy?' He assures me it's coming!"

Although Bilbo is heavily involved in the plot of the upcoming picture, Freeman doesn't see himself as the star of the film. He's more interested in telling people about how much work Jackson has put into shooting.

"I honestly don't feel that pressure, no. I really, really don't. Of course, it is Bilbo's journey, but I didn't write it. I'm not directing it... It's not my film. It's Peter's film," he said.

Freeman's fellow actor Stephen Fry has also let slip that working on The Hobbit isn't always as glamorous as it may seem. He recently told an interviewer that Jackson has made him try some interesting delicacies for his role as the Master of Laketown.



"He made me eating testicles," Fry said. "I've mustn't give too much away, but I've got a bald cap and then on top of that a really bad combover wig and this wispy moustache and wispy beard and horrible blotchy skin and disgusting fingernails."



Jackson is renowned for his love of gross and disgusting, with previous films like The Frighteners and Bad Taste high up in the gross-out stakes.



New Zealanders can get a first glimpse on the Hobbit movie tomorrow when the trailer premiers at 4pm.

The Hobbit: An Unexpected Journey is set to premier in Wellington in December next year.