Best Costar Couple

Ian Somerhalder and Nina Dobrev

The Vampire Diaries paramours took their romance public in the spring of 2011. "He always has a positive outlook and positive energy, and he's always happy,"

Liam Hemsworth and Miley Cyrus

The stars met on the set of 2009's The Last Song and have been going strong ever since. "I try to be romantic,"

Freddie Prinze, Jr. and Sarah Michelle Gellar

The couple met while filming the 1997 horror film I Know What You Did Last Summer and began dating three years later. They tied the knot in Mexico on September 1, 2002. P

Blake Lively and Ryan Reynolds

Though they were both dating other people while shooting The Green Lantern in 2010, things turned romantic the following year. By April 2012, Reynolds had "practically" moved in with Lively, a source said.

Robert Pattinson and Kristen Stewart

For years, the Twilight stars refused to acknowledge their real-life romance. "So much of my life is so easily Googled," Stewart told British GQ in 2011, finally confirming their relationship.

Goldie Hawn and Kurt Russell

Hawn and Russell met in 1968 while filming The One and Only, Genuine, Original Family Band, but they didn't begin dating until they became costars in 1983's Swing Shift. Three years later, they welcomed a son.

Brad Pitt and Angelina Jolie

Though he was married to Jennifer Aniston at the time, Pitt couldn't take his eyes off of Jolie on the set of Mr. & Mrs. Smith in 2004.

Will Smith and Jada Pinkett

Though she didn't land the part of Smith's girlfriend on The Fresh Prince of Bel-Air in 1995, Pinkett married the series star two years later.

Jennifer Aniston and Justin Theroux

Though Theroux was dating stylist Heidi Bivens at the time, sparks flew on the Georgia set of Wanderlust in the fall of 2010. Aniston and Theroux took their romance public the following spring.