<P> "Till Death Do Us Part" is the 24th and final episode of the ninth season of the American police procedural drama NCIS, and the 210th episode overall . It originally aired on CBS in the United States on May 15, 2012 . The episode is written by Gary Glasberg and directed by Tony Wharmby, and was seen by 19.05 million viewers . </P> <P> In the episode, NCIS is threatened by terrorism while Jimmy Palmer's wedding occurs . </P> <P> With Director Leon Vance reported missing, the NCIS team is called out to where his car has been found unoccupied . After investigating Vance's car, the team locates Vance at a family plot where Vance finds himself in a crypt, next to the body of a sailor killed along with the son of industrialist - turned - terrorist Harper Dearing . After picking him up, the team finds another message with a horse jaw that leads them to a retired NCIS agent who handled a case that sent Dearing's son to the destroyer that claimed his life . However, Dearing blows up the agent's house and leaves them a videotaped message, soon confronting Pentagon profiler Dr. Samantha Ryan by threatening her son and forcing her to flee when he buys out a judge to release her ex-husband on a technicality . Meanwhile, Jimmy is nervous on whether or not to go through with the marriage with everything going on and with no one else being able to attend, but Ducky tells him to go through with it, and that he will join him . However, Jimmy asks Breena to advance the wedding so he could return to assist with the case and so his friends could be there . </P> <P> Gibbs decides to recruit convicted former officer Jonathan Cole based on Ryan's profiling of Dearing to lure him into a trap . It initially seems to have worked when Dearing tells Cole to meet him a cafe retired Navy officers attend, but Dearing doesn't show up to the meeting and instead leaves a phone for Cole . The former calls and tells Cole to relay a message to Gibbs that he was never interested in Director Vance and is really interested in justice . Back at headquarters, analyzing the call makes the team realize there is a bomb in Vance's car, installed when he was abducted, meant to blow up NCIS Headquarters at the Navy Yard and the whole building is evacuated . Cole attempts to defuse the bomb but is killed in the process (assumed), when the bomb detonates, while receiving a phone call indicating the bomb was for revenge against the Navy due to the death of his son, Evan, (revealed in "Up in Smoke") damaging part of the NCIS building with Gibbs and his team still inside . Ziva and Tony are in an elevator with debris falling on them after evacuating people, Abby and Gibbs are stuck in her lab, and Tim is just leaving his desk after securing a backup drive from his computer . Ducky receives a phone call about the attack and is asked to autopsy the bodies, but the shock and stress of the call causes him to have a heart attack and collapse alone on a beach, leaving everyone's fates unknown . </P>

Ducky has a heart attack on the beach