While the team investigate a double murder out on the highway, Kate pushes Tony down and he notices a bomb on the car, saving Kate and McGee. The FBI notifies the team that Ari Haswari has returned to the US and may be on a personal vendetta to assassinate Gibbs. Gibbs, Tony and Kate search for Ari, Kate takes a bullet in the chest for Gibb’s life. She reveals that she is wearing a bullet proof vest but unannounced, Ari Haswari kills Kate with a bullet to the head, using a Bravo 51 (also known as a Kate) and the same ammunition Gibbs used when he was in the Marine Corps. Gibbs and Dinozzo are left shocked and searching for the killer, and Gibbs whispers “Ari” before the end of the episode.
When Tony opens a mysterious letter thinking it is for him, a small puff of white powder comes out, releasing a possibly deadly bacteria. Kate calls for help and as a precaution, she and Tony are put into a bio-hazard isolation room. While McGee and Gibbs are determined to discover who sent the envelope and how to cure their friends before its too late for them, Tony’s health gets worse.
The executor of a petty officer’s will discovers the skeletal remains of a missing girl in the dead man’s rented storage unit. As the petty officer is up for a silver star, it is very important that NCIS determines if he was a murderer, within 24 hours. Soil samples and further forensics lead Abby to discover that if the marine was the killer, he could not have acted alone. Tony and McGee find CCTV footage that suggests the marine was entirely innocent. Tony also has to deal with his car being stolen.
A marine is found murdered on the school campus, and the team immediately finds a suspect. However, they are forced to start again when they find the suspect murdered. McGee and Abby discover a trace in the e-mails, called “Red Cell,” which leads them to believe that the marine must have been involved in a serious death game.
The team investigates a suicide case, believing that the main reason of her death is a nervous breakdown, but Ducky believes that she was actually murdered. FBI Special Agent Fornell helps them in the investigation. The team discovers that the dead woman was involved in a love triangle and that this may have contributed to her death.
A Virginia Beach bikini contestant drowns in a public bathroom toilet. When the team discover she posed partially naked in a magazine, and was pregnant at the time of her death, clues are revealed that lead to an unlikely suspect. Tony finds a juicy secret from Kate’s past.
When a Petty Officer working in Intelligence receives a pair of cobalt blue eyeballs in the mail, the NCIS team starts investigating the case. The sailor commits suicide during the investigation and after Abby matches the eyes to a South American girl in a photo with the dead man’s lecturer, Kate and Tony must travel to the Triple Frontier destination of Paraguay to discover the truth.
A dance club bartender wakes up in bed with a dead female petty officer and claims this was not the woman he came home with, despite the fact that he was drunk at the time. DNA tests reveal that he was telling the truth, but the team must still work to figure out whether this means that he didn’t kill the dead woman. The victim’s sister and a local corrupt businessman may know more than they are telling. Guest Starring Mýa.
A Marine falls off a cliff, and his camera records him falling. The prime suspects are his wife and his best friend with whom he was staying in the camp. Gibbs finds out they had an affair behind a dead man’s back and he tries to persuade them to blame each other. In the meantime, Abby reconstructs the damaged film footage on the camera and reveals a previously dismissed suspect to have been in the vicinity at the time of the death.
A beautiful young MIT graduate (Danica McKellar) witnesses a sailor being strangled. Local police doubt her story, but McGee asserts that her account warrants further investigation. When a sailor’s body is found at another location, the story gains ground. The witness also captivates McGee who, after a sudden twist in the investigation, unknowingly holds the key to solving the case.
