Gerald Lee McRaney (born August 19, 1947) is an American television and movie actor. McRaney is best known as one of the stars of the television shows Simon & Simon, Major Dad, and Promised Land. He was a series regular in the first season of Jericho and the final season of Deadwood. He appeared in a recurring role as main antagonist Mason Wood in season eight of Castle. Recently, he played Barlow Connally in the A&E series Longmire and has a recurring role in the NBC series This Is Us as Dr. Nathan Katowski, a role which earned him the Primetime Emmy Award for Outstanding Guest Actor in a Drama Series.