X-MEN star Ben Foster needed copious amounts of coffee to keep up with a crystal-methamphetamine-addicted gang while researching his role in new film ALPHA DOG - because they stayed up for four nights running. The actor plays a dug addict opposite Justin Timberlake and EMILE HERSCH in the harrowing new film and he admits researching his role was one of the toughest parts of the job. He says, "I had a friend who was a recovering addict himself, and he dropped me into his crew that was still going pretty strong. "I went through a screening process of showing them I wasn't a narc (cop), and they let me watch them for a few months. "I'm sitting in the corner, watching them snort, smoke and shoot, and they're going on day four without sleep. I'm just jacked up on coffee, and I'd pass out." Foster also received martial arts training for the film and spent three months mastering the basics. He adds, "The person that my character was loosely based on was a national tae kwon do champion, so I got martial arts training for three months. "You hold yourself differently when you know you can destroy someone."