The team works to collect all the evidence they can in an effort to stop Ari.
Ari continues to wreak havoc on the team until Gibbs gets the face-off he has been awaiting.
Gibbs meets with a serial killer days before the man's execution to find out about missing bodies, but the inmate won't reveal the information, so Gibbs assembles a team to reinvestigate.
When a dead staff sergeant is found encased in a Civil War-era tomb, a cell-phone within it leads investigators to a safety deposit box.
Members of the NCIS squad investigate when a petty officer with a double life is gunned down on a freeway.
Two bored housewives, whose husbands are serving in Iraq, begin running an Internet sex site from their bedrooms, then both of them disappear mysteriously .
A 6-year-old boy tells the NCIS team that his father, an officer working as the Navy's liaison with a defense contractor on a highly confidential project, has been kidnapped.
When the bodies of two assassins are delivered to NCIS from overseas, Tony and Ziva go under cover to find the intended targets.
Tony is suspected of murder when part of a female body is found at Quantico, and Abby makes it her personal mission to find out who is framing him.
The team bands together to clear McGee's name when he kills an undercover police officer while on assignment.
The death of a supermodel filming a reality show on a military base first appears to be suicide, but Gibbs and his team uncover a twisted love triangle and hunt for her killer.
Tony and Ziva become trapped in a container while investigating the possibility of weapons smuggling at a shipyard.
The commander in charge of a shipment of nuclear weapons seems to have been abducted, and Gibbs and his team work quickly to find her and protect the classified location of the armaments.
When the wives of two Marines are murdered, the team fears the murders are racially motivated and works together to find the killer.
Gibbs and the NCIS team make a disturbing discovery when they bust an illegal automotive chop-shop run by Marines.
When an ambulance mysteriously explodes while transporting the remains of a Marine, Gibbs and the team find that identifying the remains is harder than they had expected.
NCIS team members search a missing Marine's campsite and realize he was not alone, so they search for his camping partner, a woman who may still be alive.
A teen at a high school on Quantico Marine Corps Base attaches a bomb to his body and holds his fellow students hostage.
Gibbs and the team investigate when the body of a missing Marine is found in a frozen lake.
Gibbs and his team must investigate the apparent suicide of a Pentagon cryptographer some suspected of spying.
Abby becomes the target of a stalker, sending the team into protective overdrive, searching for the person who is out to get her.
Ziva finds herself under investigation for the death of a suspect; Director Shepard is kidnapped.
Gibbs' long-suppressed memories overwhelm him as he recovers from injuries he sustained in a terrorist bombing.