Reese Witherspoon has signed on to play a giant in a new animated battle movie Monsters vs. Aliens.

According to Hollywood.com, the Oscar-winning actress will team up with Hugh Laurie, Seth Rogen and Kiefer Sutherland, among others, to voice quirky characters in Dreamworks' upcoming film.

Witherspoon's character, Susan Murphy, becomes a 50-foot monster, dubbed Ginormia, after she's hit by a meteor from outer space. She's then captured by the U.S. military and taken to a top-secret compound, where other 'monsters' are kept.

These include the insect-headed Dr. Cockroach (Laurie) and half-ape/half-fish Missing Link (Will Arnett). Sutherland will voice the aptly named General W.R. Monger. The monsters team up to attack invading aliens.

Monsters Vs. Aliens was released March 27th, 2009 and stars Reese Witherspoon, Seth Rogen, Hugh Laurie, Will Arnett, Kiefer Sutherland, Rainn Wilson, Stephen Colbert, Paul Rudd. The film is directed by Rob Letterman, Conrad Vernon.