06/07/2012 04:37 pm ET Updated Jun 07, 2012

Mary-Kate & Ashley Olsen Movies: Megan Fox & 9 Other Celebrities Who Starred With The Twins (VIDEO)

Before Michael Cera was defeating evil boyfriends in "Scott Pilgrim" or being anxious in "Arrested Development," he was just a whiny kid -- with "very delicate bone structure" -- in a Mary-Kate and Ashley Olsen movie.

Cera's not the only Hollywood star to get his start in an Olsen movie. "Transformers" starlet Megan Fox wasn't always breaking hearts and taking names. In 2001's "Holiday in the Sun" -- Fox's film debut -- the future on-screen vixen was a total mean girl, out to ruin Mary-Kate and Ashley's fun in the sun.

Future "House" star (and Aussie) Jesse Spencer played a handome Brit who romanced Mary-Kate in 2001's "Winning London," while "One Tree Hill" stud Austin Nichols also had his eye on Mary-Kate in "Holiday in the Sun."

Click through the gallery below to see more famous faces in Mary-Kate and Ashley Olsen movies.

Famous Faces in Mary-Kate & Ashley Movies