A later episode had members of the NCIS team discovering Gibbs’ big secret (murder), leading to Mark Harmon’s character having a long and meaningful talk with his therapist, Laura San Giocomo’s Dr. Grace Confalone.
Gibbs then capped the season off by once again hallucinating his dead wife in the time span just before Ziva showed up.
“She” was also where NCIS revealed that Ziva was not only supposedly still alive, but she was tracking a cold case and keeping a small office inside a storage unit.