"There were moments where I knew I needed to get on the right course. Very sobering moments. As a 17-year-old adolescent hearing the jail door slam behind you, that's a very sobering moment. I had a very specific moment where I knew I needed to change my life, but when you decide to change your life then actually doing it, that becomes a very challenging and uphill battle that you need to take on a day-to-day basis." Actor MARK WAHLBERG on deciding to turn his life around after spending time in prison for assault as a teen.