The Last Link is the 12th episode of NCIS Season 16 and also the 366th episode of the entire NCIS series.
An old family friend, Army Corporal John Sydney, beseeches Gibbs to join him on a road trip to search for a missing military I.D. bracelet while the rest of the team investigate when a Navy Lieutenant who was in protective custody is fatally poisoned by an infamous drug dealer.
- Gibbs' namesake, Medal of Honor recipient L.J. Moore, passed away prior to the events chronicled in the episode.
- It is revealed that Jackson Gibbs participated in the Invasion of Normandy while serving in the US Army Air Forces.
|Leroy Jethro Gibbs||Mark Harmon||Special Agent in charge of the NCIS Major Case Response Team.|
|Timothy McGee||Sean Murray||Senior Special Agent and second-in command of the NCIS Major Case Response Team.|
|Nicholas Torres||Wilmer Valderrama||Special Agent for the NCIS Major Case Response Team.|
|Eleanor Bishop||Emily Wickersham||Special Agent for the NCIS Major Case Response Team|
|Jacqueline Sloane||Maria Bello||NCIS Forensic Psychologist|
|James Palmer||Brian Dietzen||Medical Examiner for the Major Case Response Team|
|Kasie Hines||Diona Reasonover||NCIS Forensic Specialist; Abby's replacement|
|Leon Vance||Rocky Carroll||Director of NCIS|
|Donald Mallard||David McCallum||Chief Medical Examiner for the NCIS Major Case Response Team. Despite being credited, McCallum doesn't appear in this episode.|
|John Sydney||Dabney Coleman||Army Corporal, World War II veteran, and longtime friend of the Gibbs family from Stillwater, PA|
|Tommy Mulligan||Luke Edwards||AKA "Peaches".|
|Ross Johnson||Johnny Wactor||Navy Lieutenant|
|Oliver Sherry||Sam Littlefield|
|Cal Fraser||Daniel E. Smith||Current owner & operator of the Stillwater General Store, given to him by Gibbs after the latter's father's death.|
|Megan Boone||Rochelle Robinson|
|Michael Deegan||Ian Duncan||Notorious drug dealer and suspect in the Ross Johnson murder.|
|Anna Ventura||Lisa Maley||NCIS Probationary Agent.|
|Burly Bodyguard||Jess Allen|
|Uniformed Room-Service Guy||Adam Aguirre|