Radio Times

• Episode 1/24 Kill Ari (Part 1)

  Kate is dead at the hands of a sniper. Each member of the team is determined to find her killer and each faces visions of Kate as they try to cope with her death. A new NCIS director, Jenny Shepard, wants to stop Gibbs hunting down Ari - and so does Ziva David, a new Mossad agent assigned to help the hunt. But are her loyalties divided?

• Episode 2/24 Kill Ari (Part 2)

  Ari kidnaps Ducky in an attempt to throw Gibbs off the trail - but Gibbs, suspecting Ari is somehow connected to new agent Ziva, plans to use her to track Ari down. Unfortunately, he has no idea just how closely linked they are… And as everyone continues to be plagued by visions of Kate, Gibbs comes to fear for the sanity and safety of his entire unit.

• Episode 3/24 Mind Games

  A serial killer Gibbs caught years ago is finally about to be executed - but he wants to see Gibbs first, claiming he'll reveal where his missing victims are buried. Gibbs knows it's a lie but, forced to interview the condemned man on Death Row, soon finds himself recalling the horrors of the original case.

• Episode 4/24 Silver War

  A perfectly sealed Civil War sarcophagus is discovered - containing a corpse that may be a modern-day marine and a mobile phone that's unlikely to be a period artefact. Gibbs is told to accept Mossad agent Ziva as a permanent new member of his team, but despite his orders he'll only allow her to observe. As the case becomes more intricate, attention turns to the mobile phone and the last call made on it.

• Episode 5/24 Switch

  For once, the team appear to have a straightforward case. An officer is shot dead on the freeway and it seems clear the killing is related to events in his personal life, not a military matter. But the dead man has been leading a double life - and when the investigators learn of his dying words, everything changes.

• Episode 6/24 The Voyeur's Web

  How hard can it be to solve a murder committed live on the internet? But all the online evidence doesn't prevent the case becoming incredibly complex. The apparent murder victim is a marine's wife but the case is tied to a live internet sex site - and now more housewives are missing. Gibbs must find them, and the only way to do that is to uncover who's really running the website.

• Episode 7/24 Honor Code

  A little boy reports that his father, a military officer, has been kidnapped. The team learn that the missing man is in charge of top-secret project Honor - indeed, he's the only person who has the codes to access it. So when they discover that all the project data has been deleted, they have to ask themselves whether the man is a victim or a criminal.

• Episode 8/24 Under Covers

  Two assassins arrive at the NCIS office - or rather, their bodies do. Unable to determine who hired the killers, Tony and Ziva go under cover as their intended victims. Isolated from the rest of the team, and staying in a fancy hotel, their usual banter becomes charged. In the meantime, Gibbs suspects that NCIS isn't the only agency involved in the plot.

• Episode 9/24 Frame-Up

  An NCIS officer could have the know-how to get away with murder - but he could also be someone likely to have enemies trying to frame him. Tony has been accused of a killing and as fact after fact points to his guilt, it's down to Gibbs and his colleagues to uncover the truth. But Tony is just the man you'd call on to investigate this kind of case - so the team is short an expert as well as short on time.

• Episode 10/24 Probie

  With the investigation against Tony at an end, the team abruptly finds itself questioning another of its own. McGee admits that he killed a man, but says it was in the line of duty. Unfortunately, the victim was an undercover police officer. NCIS director Jenny Shepard assigns Gibbs's team to the case, despite possible conflicts of interest - and definite conflict between Gibbs and Shepard.

• Episode 11/24 Model Behavior

  It could be Tony's ideal case: the NCIS team has to investigate the murder of a supermodel which will, of course, entail interviewing all her colleagues. She was taking part in a reality TV show being filmed on a military base, which is why the crime falls within NCIS jurisdiction. But it soon becomes clear she was also involved with several men, who are all strong suspects.

• Episode 12/24 Boxed In

  Nobody would be too surprised if Tony and Ziva were to go off alone together - but in the middle of an investigation? And Abby can't even find them when she does the standard GPS check on their phones. As the NCIS team search a shipyard where the two were looking for smuggled weapons, Tony and Ziva are in trouble and hiding in a container - and might just have stumbled upon the key to the case.

• Episode 13/24 Deception

  The NCIS is thrown into a new kidnapping case and this one is seriously against the clock. A commander in charge of nuclear supply shipments for power stations has been abducted. But is her role the motivation for the kidnapping? Whatever the reason, the NCIS team must get to her before the criminals learn where the fuel rods are being kept.

• Episode 14/24 Light Sleeper

  Who'd marry a marine? The wives of two officers are murdered and although it doesn't look as if the deaths are related to the men's military background, the unit is obliged to investigate. Gibbs comes to suspect that the real motivation is racial. And if he's right, a third woman is surely the next target. Can the team protect her and her baby while tracking down the culprit?

• Episode 15/24 Head Case

  Marines are very highly trained in the driving and handling of cars so it's no great surprise when Gibbs and the team learn some are running their own repair garage for profit. And it's not much more startling when they discover that all the cars are stolen. But things do take a shocking turn when one marine's disembodied head is found in a car. It's not long before every marine running the shop is cleared of the crime - so who did it?

• Episode 16/24 Family Secret

  An ambulance carrying the remains of a dead marine suddenly explodes - and when the NCIS team comb through the debris, a routine DNA check reveals that the body is not who they thought it was. Gibbs now faces two challenges: to find out who bombed the ambulance - and discover who the victim really was.

• Episode 17/24 Ravenous

  Teenagers out hiking discover military dog tags that the NCIS unit connect to a marine who went missing while camping in the area. It looks like someone else is missing too and the team learn that the area has seen several similar cases in the past. Could there be a serial killer at work? And if he or she has evaded law enforcement for this long, can the NCIS squad really uncover the truth?

• Episode 18/24 Bait

  The NCIS must deal with a suicide bomber at a military base's high school: a student has taken his peers hostage and is threatening to blow up the bomb he's wearing. While Gibbs and the sniper teams get in close, Tony is left to run the operation from outside. And as the clock ticks, Gibbs begins to suspect the student is being manipulated by someone else outside the school.

• Episode 19/24 Iced

  Marine discipline meets street gang violence as a missing soldier's body is discovered deep in a frozen lake. A standard crime scene search proves difficult because of the conditions but it's worth it - three more bodies are found. What's more, the new victims all had distinctive tattoos, so it will be easy to find their gang. It's just going to be harder to uncover their connection with the marine.

• Episode 20/24 Untouchable

  When is a death suicide and when is it murder? The NCIS team investigate the case of a Pentagon officer who appears to have killed herself. Everything hinges on whether there was someone else with her. When they prove there was, the case becomes a hunt to find what happened, who this other person was - and why the officer had to die.

• Episode 21/24 Bloodbath

  There are echoes of events the previous year as it becomes clear someone is again targeting a member of Gibbs's NCIS team. This time it's Abby, who's almost killed when investigating evidence from what had appeared to be an unremarkable murder case. Now it looks like that murder was committed solely to get to Abby - but who's after her?

• Episode 22/24 Jeopardy

  The brother of a suspect the NCIS team have in custody demands his release - but the man is dead. When it looks as if Ziva is indirectly responsible, the team closes ranks to protect her. But the brother is much more thorough than Gibbs expects and it isn't Ziva that he targets. Can Gibbs protect NCIS director Jenny Shepard and Ziva at the same time?

• Episode 23/24 Hiatus (Part 1)

  It's time to find out a little more about Gibbs and his painful hidden past. After he's severely wounded during an op and lies unconscious in hospital, the bad memories come flooding back. While Gibbs regrets the things he has and has not done in his life, Tony takes charge of the NCIS team and learns just how hard a job that really is.

• Episode 24/24 Hiatus (Part 2)

  We've had an intriguing glimpse of Gibbs's past but now he's regained consciousness in hospital, it seems the past is all he has: he cannot remember the explosion, Ducky or NCIS. The last 15 years of his life are gone and as he tries to piece it all together, the NCIS investigators come up with some surprises about Gibbs themselves.

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