The trailer for NCIS: Origins has arrived. The CBS show is a prequel that is part of the sprawling NCIS universe and set in 1991, during the time when Mark Harmon’s character Leroy Jethro Gibbs, played as a younger man by Austin Stowell, first became a special agent at the NIS Camp Pendleton office. Harmon will remain a part of the upcoming NCIS: Origins as the show’s …