(Cover) - EN Showbiz - 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, Martin doesn't see himself as the star of the film. He's more interested in telling people about how much work Peter 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.

The Hobbit: An Unexpected Journey is slated to hit screens late next year. (C) Cover Media