Season 2 Finale: "Twilight"
Leave it to Anthony DiNozzo to return to work early after nearly being killed. Fresh off medical leave, DiNozzo came back to the NCIS office just in time to head to a crime scene with his colleagues, Kate Todd and Timothy McGee. That's where he noticed something suspicious: a bomb in the trunk of the car they were investigating.
He warned McGee just in time for the agents to take cover. Later, they learned the bomb wasn't intended for the victims, Navy Lieutenants Dean Westfall and Curtis Janssen, but for them. Who would try to kill NCIS agents? It turned out to be Leroy Jethro Gibbs' long-lost enemy, terrorist Ari Haswari.
FBI Agent Tobias Fornell knew of Gibbs and Haswari's troubled relationship, but he still refrained from warning Gibbs that the terrorist was back in the United States. In the meantime, Haswari had already grabbed one of the victim's drones--by using his severed hand to get access--and loaded it with explosives. Turns out Haswari was leading an Al-Qaeda terrorist mission the whole time.
The NCIS team hustled over to a warehouse in Norfolk, where a large group of Marines were scheduled to return home. As they searched for Haswari, Kate took a bullet to protect Gibbs. Surviving the initial hit, she stood back up-- only to have Haswari shoot her through the head.
The episode ended with Gibbs searching for Haswari ...