Sophia Bush

Biography: This former Tournament of Roses Parade Queen caught the acting bug in high school and started landing small movie parts in her early twenties. After a recurring role as a bisexual teen on Nip/Tuck, Bush came to prominence as sexy Brooke Davis on One Tree Hill in 2003, and while the show was on hiatus, she took on some big-screen roles in films such as John Tucker Must Die. However, it was her off-screen antics that won her the most attention. After a whirlwind romance with her One Tree Hill costar Chad Michael Murray, the two married and separated in 2005, yet continued to play on-screen lovers. Murray and Bush's characters eventually followed their real-life counterparts and broke up, but Bush continued to date other costars off screen: In 2008 she dated James Lafferty, and by 2009 she was dating Austin Nichols. She's also branched out beyond just acting by campaigning for Barack Obama in the 2008 presidential election and directing several episodes of One Tree Hill.