Shark (2006)

Sebastian Stark, a charismatic, supremely self-confident defense attorney who, after a shocking outcome in one of his cases and a personal epiphany, brings his cutthroat tactics to the prosecutor's office as the head of the Los Angeles District Attorney's High Profile Crime Unit. A group of young prosecutors are about to have the learning experience of a lifetime because, though Stark is seeking to redeem himself, he has no intention of cooling his underhanded approach to cases just because he's now working for the "good guys."