Season 4 - Episode 1 : Shalom Sep 19, 2006
Season 4 - Episode 1 : Shalom Sep 19, 2006
The NCIS team must learn to work without Gibbs, who has retired; Ziva witnesses a political assassination and the FBI wants her.
Season 4 - Episode 2 : Escaped Sep 26, 2006
NCIS temporarily reinstates Gibbs when an escaped convict threatens his friend's life.
Season 4 - Episode 3 : Singled Out Oct 3, 2006
While searching the abandoned and bloody car of a missing Navy lieutenant, the team learns she had been profiling men to find the perfect mate.
Season 4 - Episode 4 : Faking It Oct 10, 2006
The team is called to the scene of the murder of a petty officer who was part of an undercover arms operation.
Season 4 - Episode 5 : Dead and Unburied Oct 17, 2006
The team investigates the death of a missing lance corporal, whose body was buried in the backyard of a vacant house and then exhumed.
Season 4 - Episode 6 : Witch Hunt Oct 31, 2006
The NCIS team investigates when a Marine is attacked in his home and his daughter is kidnapped on Halloween; Abby's Halloween costume leaves McGee and Tony speechless.
Season 4 - Episode 7 : Sandblast Nov 7, 2006
Gibbs' team works with the Army Criminal Investigative Unit to investigate a suspected terrorist attack that killed a Marine colonel at a military country club.
Season 4 - Episode 8 : Once a Hero Nov 14, 2006
Suspicious activity surrounds a decorated Marine veteran's death, leading the NCIS team to try to clear his name.
Season 4 - Episode 9 : Twisted Sister Nov 21, 2006
McGee takes things into his own hands, forgoing NCIS procedure, when his sister arrives on his doorstep, bloodied and confused.
Season 4 - Episode 10 : Smoked Nov 28, 2006
The NCIS team joins forces with the FBI when a burned and mummified body found in a furnace turns out to be that of a serial killer the FBI had been chasing for more than a decade.
Season 4 - Episode 11 : Driven Dec 12, 2006
A highly classified robotic vehicle causes the death of a Navy lieutenant working on a high-level project for the Department of Defense; Tony's secretive trips to the hospital worry Ziva.
Season 4 - Episode 12 : Suspicion Jan 16, 2007
The team battles local biases when it investigates the murder of a high-level Marine intelligence officer found in a small-town motel room.
Season 4 - Episode 13 : Sharif Returns Jan 23, 2007
The NCIS team must track down a wanted terrorist (Enzo Cilenti) who has obtained a missing chemical weapon before he carries out his plan to attack major U.S. cities.
Season 4 - Episode 14 : Blowback Feb 6, 2007
Ducky goes under cover to stop the illegal sale of the Navy's top-secret weapons system to a high-priority arms dealer (Armand Assante).
Season 4 - Episode 15 : Friends and Lovers Feb 13, 2007
When a young sailor's body is found in an abandoned building in a seedy part of town, an ominous message written in blood leads the team to switch gears to find the killer.
Season 4 - Episode 16 : Dead Man Walking Feb 20, 2007
The NCIS team suspects foul play when a Navy lieutenant is the victim of radiation poisoning; Tony sees a softer side of Ziva.
Season 4 - Episode 17 : Skeletons Feb 27, 2007
When an explosion at a military cemetery's mausoleum reveals a cache of dismembered human remains, the team searches for a potential serial killer.
Season 4 - Episode 18 : Iceman Mar 20, 2007
With a young Marine on life support, the team tracks his movements in the days leading up to his being left for dead.
Season 4 - Episode 19 : Grace Period Apr 3, 2007
Cassidy (Jessica Steen) blames herself when the team learns that a tip on terrorist activity was a trap that resulted in the deaths of two agents.
Season 4 - Episode 20 : Cover Story Apr 10, 2007
When a petty officer on whom McGee based a character for his latest book is murdered, McGee must figure out who could have accessed his secret manuscript.
Season 4 - Episode 21 : Brothers in Arms Apr 24, 2007
Gibbs and the team must take action after the director's risky solo meeting with an informant ends with a death.
Season 4 - Episode 22 : In the Dark May 1, 2007
The team turns to a blind photographer (John Billingsley) to use his heightened senses of hearing and smell to re-create a crime scene and track down a petty officer's killer.
Season 4 - Episode 23 : Trojan Horse May 8, 2007
Gibbs leads the investigation into a murder victim found in a taxi headed to NCIS headquarters; Jenny discovers a secret about her past.
Season 4 - Episode 24 : Angel of Death May 22, 2007
Upon the director's return from a European junket, the team's secrets unravel; a merciless drug dealer holds Dinozzo and his girlfriend captive.