By Mandi Bierly
Updated March 03, 2010 at 10:55 AM EST

Jason Isaacs, one of pilot season’s most sought-after stars, has signed on to the Fox drama Pleading Guilty, based on Scott Turow’s book of the same name. According to The Hollywood Reporter, he’ll star as Mack, a “cop-turned-attorney described as ‘a big handsome Irish lunk'” who investigates the disappearance of a law firm’s top litigator. Isaacs, who previously starred in Showtime’s Brotherhood and the Harry Potter films, will next appear opposite Matt Damon in Green Zone.