Tribes is the eleventh episode of Season Five and also the 105th episode of the NCIS series.
The team investigate when the body of a Muslim Marine is discovered near a mosque that the FBI suspect is guilty of terrorist recruitment. Examinations soon reveal that the victim was shot and then poisoned. However, the investigation threatens to grind to a complete halt when the victim's father begs Ducky not to perform an autopsy due to the fact that if Ducky does, then the victim himself will never find any peace in Heaven. Further investigation leads the team to a terrorist who is known as the Recruiter who may be responsible for the Marine's death.
In a mosque, various Muslims are engaged in prayer while Abdul Bakr looks deeply conflicted.
The leader of the prayers then heads to a podium and remarks that Allah, in his wisdom and greatness has given us each a gift, a gift they must share with others, even if they do wish to accept it.
In the crowd, Bakr is restless.
The leader then remarks that it is their obligation to share Islam with non-believers so that they may save them from themselves.
Bakr looks back and forth, obviously paranoid over something.
In the crowd, Bakr rubs his eyes.
A while later, everyone exits the mosque although some are hanging around, talking to each other and as Bakr heads off, he glances back and forth.
In a street, Bakr looks back and sees someone who's wearing a hood following him.
This has Bakr increasingly agitated.
Sometime later, Bakr turns into an alleyway and hides against a dustbin but he collapses to the ground, revealing himself.
The hooded figure arrives in, standing in front of Bakr.
Bakr draws his gun and attempts to fire, only for the poison that has been flowing through him to take control, causing Bakr to drop the gun to the ground.
With Bakr dead, the hooded figure grabs the gun and shoots Bakr in the neck before removing Bakr's ring, watch and wallet while also leaving the gun behind.
It then cuts to a close-up of the chains around Bakr's neck, revealing that they are dog tags and that Bakr is in fact a Marine.
NCIS Special Agent Anthony DiNozzo arrives in for work, even greeting a female passer-by before he heads to his desk.
As he does so, throwing his coat and backpack over to where his desk is, he spots his partner, NCIS/Mossad Liaison Officer Ziva David watching something on her computer which prompts him to call Ziva's name although Ziva shushes him.
- Brent Langer, an Agent with the FBI is introduced for the first time.
- It's revealed that Abby likes to give her lab the nickname, "Labby".
|Leroy Jethro Gibbs||Mark Harmon||NCIS 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||Mossad Liaison to NCIS and also a member of the NCIS Major Case Response Team.|
|Timothy McGee||Sean Murray (actor)||NCIS Junior Special Agent and a member of the NCIS Major Case Response Team.|
|Abigail Sciuto||Pauley Perrette||Forensic Specialist, NCIS.|
|Jennifer Shepard||Lauren Holly||Director of NCIS.|
|Donald Mallard||David McCallum||Chief Medical Examiner, NCIS.|
|James Palmer||Brian Dietzen||Ducky's assistant.|
|Khalid Mohammed Bakr||Shaun Toub||Abdul Bakr's father.|
|Brent Langer||Jonathan LaPaglia||An FBI agent who was originally a member of Gibbs's own team.|
|Ryan Sikes||James Parks (actor)||A man who appears in the episode.|
|Jim Mills||David Haydn-Jones||A man who appears in the episode.|
|Donna Dunlap||Jennifer Hetrick||A woman who appears in the episode.|
|Sunni Man||Fred Toma||A man who appears in the episode.|
|Abdul Bakr||Walid Amini||The main murder victim.|
|Stevedore||Maria Zambrana||A woman who appears in the episode. Uncredited role.|