NCIS: Naval Criminal Investigative Service Episode 2.23 Twilight

While the team investigate a double murder out on the high-way, 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 Gibbs 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) & 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.