"The members of NCIS are distressed when Gibbs is injured in a terrorist explosion while on assignment."

"As the team tries to track down the terrorists behind the bombing that injured Gibbs, they learn that the terrorist group is planning another bombing of 9-11 magnitude--and that Gibbs has information about their plan."

"As each team member deals with the absence of a retired Gibbs, Ziva's past comes back to haunt her when she inadvertently witnesses the assassination of a military attaché by her former Mossad partner."