With the premiere of NCIS: Origins just around the corner, the shows creators have revealed in interesting detail about Mark Harmons involvement in the prequel series. Known for his iconic portrayal of Leroy Jethro Gibbs, Harmon will not only be narrating the series, but hes also had a pivotal role to play behind the scenes. NCIS: Origins stars Austin Stowell as a younger version of Gibbs and is all set to deliver a fresh take on the characters early years at NCIS.