Robert Downey Jr. is considered by many to be one of the finer actors working today, but he confessed that he worried that his past history of drug abuse might have kept him from playing Tony Stark in the upcoming Iron Man. Speaking to, the actor admitted his fears.

"I'd never had an opportunity to do something like this that I thought could be so good and with the right people," Downey said. "I felt like I might not get a shot at doing it because of the wreckage of my past, even though it had been long enough, in my eyes," he added.

Despite his history of drug use, Downey is respected by many for his work as an actor, and was nominated for an Oscar for his role as Charlie Chaplin in Chaplin.

Ironically, some fans find Downey more suited to play Tony Stark because of his drug abuse. In the comics, Tony Stark is an alcoholic, and the character's battles against alcoholism have been as challenging for him as any battle with a supervillain.

Iron Man, starring Robert Downey Jr., Terrence Howard, Jeff Bridges and Gwyneth Paltrow flies into theatres on May 2, 2008.