Harmon's character, Naval Criminal Investigative Service Special Agent Leroy Jethro Gibbs, shot double agent Ari, played by Rudolf Martin, at the end the first season.
Ari, however, did not die and returns for the season two finale that airs Tuesday night. By the end of the episode, one member of the "NCIS" team will go down, creator Don Bellisario told Zap2it.com
Bellisario said he has taken extraordinary efforts, including shooting two endings to "NCIS," to keep the identity of the killed-off character secret.
Harmon, whose "St. Elsewhere" character died, said he joked about it when asked if the same would happen to his "NCIS" role.
"We're all personally hoping it's us, because we're all so tired, we're hoping we're going to get killed," Harmon said.