Origins so far. And while it is exciting to see Harmon return to his role again, and even briefly on-screen in NCIS: O

Warning: SPOILERS for the NCIS: Origins two-part premiere “Enter Sandman” are ahead!

Mark Harmon remains an important component of the NCIS Universe, even though he is no longer starring on the flagship show. NCIS fans already knew Mark was part of the new prequel show, but nearly everyone thought it would only be behind the scenes.

Origins season 2, episode 3, "Bend, Don't Break" In a clever twist, some of Austin Stowells worst traits as the young Gibbs character in NCIS: Origins became Mark Harmons best traits in the flagship series.

Long running series 'NCIS' spawns another spin-off with 'NCIS: Origins,' which delves into Gibbs' early years.