Shell Shock Part 1 is the sixth episode of Season Ten of NCIS and the 216th episode of the entire NCIS series.
A Lieutenant in the Marine Corps who recently returned home from the Middle East is found dead after being brutally attacked and beaten, prompting the NCIS team to investigate the circumstances surrounding the Marine's death but the team soon discover that all is not what it seems and that one suspect could be linked to a terrorist group.
As a train goes past a series of apartment buildings, its horn loudly echoing into the night, two men are busy running through the street.
It then shows that the two men are being chased by a group composed of three individuals.
The group then grab First Lieutenant Michael Torres as his friend, Captain Joe Westcott looks on, horrified.
Westcott then turns around just in time to see a hooded man emerge with the man sending Westcott to the ground.
Almost immediately, the two groups begin delivering a series of vicious blows to both Torres and Westcott.
Seconds later, the screen goes black with Torres yelling "Captain!".
It then snaps back into view with Westcott watching as the men continue beating up Torres while another blow knocks Westcott out again.
The group then deliver a series of blows to Westcott before they split up, two fleeing while two more run back to Torres.
Westcott looks up to see two men dragging Torres away as Torres yells, "No! Don't!".
"Joe!", Torres yells.
As the men drag Torres into the darkness, Torres yells, "Captain!".
"Torres!", Westcott yells.
But there's no reply.
It then cuts to Westcott who runs off into the night.
As Captain Westcott sits in Interrogation, Gibbs, Tony and Ziva in Observation examine him with Tony remarking that the Captain does seem out of it.
Ziva believes that Captain Westcott may be in shock but Tony suspects that Westcott's guilty.
Gibbs asks for the background.
Ziva then says that Captain Joseph Westcott and Lieutenant Michael Torres were close, having been friends since childhood before joining the Corps together.
Tony remarks that the records are spotless and that both men are highly regarded by their unit.
Ziva picks up by telling Gibbs that their C.O- commanding officer called them born leaders and that they exemplify the highest level of commitment to the Marines.
|Leroy Jethro Gibbs||Mark Harmon||Special Agent in charge of the NCIS Major Case Response Team|
|Anthony DiNozzo||Michael Weatherly||Senior Special Agent and second-in-command of the NCIS Major Case Response Team.|
|Ziva David||Cote de Pablo||Junior Special Agent of the NCIS Major Case Response Team.|
|Timothy McGee||Sean Murray (actor)||Special Agent of the NCIS Major Case Response Team.|
|Abigail Sciuto||Pauley Perrette||Chief Forensic Specialist of the NCIS Major Case Response Team.|
|James Palmer||Brian Dietzen||Medical Examiner Assistant.|
|Leon Vance||Rocky Carroll||Director of NCIS. Despite being credited, Rocky Carroll does not appear in this episode.|
|Donald Mallard||David McCallum||Chief Medical Examiner of the NCIS Major Case Response Team.|
|Joe Westcott||Brad Beyer||A Captain in the United States Marine Corps who is also suffering from PTSD.|
|George Westcott||Mark Rolston||Joe and Evan's father.|
|Evan Westcott||Glen Powell||Joe's younger brother and a Sergeant in the United States Marine Corps.|
|Randall J. Kersey||David Hoflin||A man who is later revealed to be a member of the terrorist group IJI.|
|Peter Sanger||Chris McGarry||Lieutenant Commander in the United States Navy and also a Doctor.|
|Sam Mathis||Vinicius Machado||Suspect.|
|Andrea Aldridge||Doris Morgado||Victim's fiancée.|
|Michael Torres||Hector Atreyu Ruiz||Main murder victim and a First Lieutenant in the United States Marine Corps.|
|James Hall||Marc Anthony Samuel||Private First Class in the United States Marine Corps.|