Adam Campbell's "NCIS" character, who has appeared on the mothership in flashbacks as the young version of David McCallum's Ducky, is sent to work with our "Origins" team to see if they need an in-house medical examiner. But the crew at Pendleton is skeptical of his true motives.

Besides the central actors Austin Stowell, Kyle Schmidt, and Mariel Molino, Philip Winchester and Adam Campbell are slated to join NCIS: Origins Season 2 as guest actors

“He always had a way of knowing who I was meant to be.” So says Mark Harmon in the emotional voiceover that caps off the NCIS: Origins serving as a tribute to the late David McCallum, with Adam Campbell reprising his role as the young Ducky.