The CSI star, who left the CBS procedural hit in 2009, will become a Season 2 series regular on WGN's Manhattan.
Petersen will play Colonel Emmett Darrow,"the enigmatic new ranking military officer at Los Alamos," the New Mexico setting for the drama that focuses on World War II scientists hurrying to build the world's first atomic bomb.
09:00 'General Hospital' star Carolyn Hennesy hopes Daytime Emmys will focus more on winners, less on politics15
00:58 Derek Jeter brings big-time star power to the Marlins' new ownership group17
16:52 NASCAR star Dale Earnhardt Jr. to retire at end of season14
13:49 Dale Earnhardt Jr. retiring at end of 2017 NASCAR season26