Will Ferrell signed up to 'Casa de mi Padre' because of a sex scene.

The 'Other Guys' star admits he instantly fell in love with Andrew Steele's script for the new Spanish comedy, 'Casa de mi Padre' - which also stars Gael Garcia Bernal and Diego Luna - because of the ''hysterical'' sex scene he has with a dummy.

''I read it and I thought it was so funny to do this epic passionate love scene, then it's just way too many shots of butts for way too long. I just thought you've never seen that, that's hysterical.''

Ferrell plays Armando, the son of a Mexican rancher who gets caught up in a world of drug-dealing villains, and the 'Elf' actor reveals he feels ''fortunate'' to be able to take on such unusual roles.

He added to Buzzinefilm.com: ''I feel fortunate enough that the stuff I do see on TV, when it's played on cable, I do stop and it still makes me watch, still makes me laugh. But this one ranks up with one of the craziest things I got to do. You can only be so lucky to be in a situation to take risks like this.''