Joseph Gordon-Levitt's new film Premium Rush has had its premiere in New York City, where the film is set.
Gordon-Levitt plays a bike messenger who finds himself carrying a suspicious package that catches the attention of a "dirty cop".
The 31-year-old actor told reporters on the red carpet that he had been in training for the role.
"I rode a bike everyday for six weeks leading up to the shooting and then rode everyday for a couple of months," he said.
Premium Rush also stars Michael Shannon and Jamie Chung, it is in UK cinemas from September 14.