Anna Faris filming "I Give It A Year" on May 20, 2012. Credit: BAUER-GRIFFIN.COM

Anna Faris may be pregnant, but she's not taking it easy!

Eleven days after announcing that she and husband Chris Pratt, 32, will welcome their first child this fall, Faris, 35, shot scenes for her new movie I Give It a Year in London Saturday. The film also stars Simon Baker, 42, Rose Byrne, 32, and Rafe Spall, 29.

For the role, bleach blonde Faris dons a long brown wig with bangs. The actress concealed her baby bump with an olive green jacket. I Give It a Year is being directed by Dan Mazer, who executive produced Faris' most recent movie, The Dictator (costarring Sacha Baron Cohen).

"I love that it's very British in that all of the dialogue is very quick, and witty, and fun to say, and it's all very dialogue-based humor. There's nobody slipping and falling on a f-cking bra or whatever," Faris tells Vulture of I Give It a Year. "So that's a great sort of change of pace."

"It's been a while since I've done a movie with three other really professional, amazing actors," Faris adds. "It's really rewarding to sit around and laugh and play with these people who are all so good at what they do."