Zac Efron Videos: Talk about his upcomming movie 'The Lucky One': cWe're sure fans of Zac Efron won't mind seeing him all muscled up for his next film, "The Lucky One," based on the Nicholas Sparks book of the same name. Not only did Efron get buffed up for the role, but he also shaved off his signature locks to play a marine who, after three tours in Iraq, returns home to North Carolina to look for the unknown woman he believes was his good-luck charm while he was fighting in the war abroad.

"It was hard, man," Efron recalled about his training for the film when he spoke to MTV News on the Golden Globes red carpet Sunday night (January 16). "I knew that the second I went to Camp Pendleton and met these real marines, I didn't have that presence."

So what kind of presence did Efron have to achieve in order to play Logan Thibault in the Scott Hicks-directed film, set for 2012 release? "They've got this way about them, but they're, like, 50 pounds heavier, so I started training immediately to do the best I could," he explained. " 'Cause it's a kind of sensitive part. I care too much about it to let it slide. I really wanted to put in the work.

The film follows in the more serious direction Efron has been taking in his roles as of late. Last year, he starred in "Charlie St. Cloud," but he will return to the world of romantic comedies when he stars in the ensemble rom-com "New Year's Eve" in December.