Season 12 of NCIS closed with Agent Gibbs shot by "The Calling" and lying bleeding in the street. Fans were relieved to hear that he will be back in season 13. Fans were also all aflutter about which agent will be returning to the crime drama come season 13.

Showrunner Gary Glasberg explained to TV Line that Gibbs will recover in the first episode of season 13, and be back with the team within a few episodes, with a new perspective attributed to his physical and psychological changes.

According to Glasberg, "But he [Gibbs] goes through a really traumatic experience in this that changes him ... The whole first half of the show is this emotional roller coaster ride of Gibbs' surgery ..."

Before Gibbs recovers, however, he will float in and out of consciousness and experience hallucinations again (mainly of his late colleague and mentor Mike Franks (Muse Watson) who was killed in season 8).

"You have to remember that Gibbs is in a difficult place," Glasberg told TVGuide.

"He's going to see some things and talk with some people that might surprise everybody. It's no surprise that Mike is there, but there are some other people from his past who he also interacts with, in some really touching scenes."

Glasberg teased that some past characters will return to NCIS although he declined to pinpoint whom. He said that one old friend will resurface in episode two to share something about Gibbs past with the team.

One important person from Gibbs' past that Glasberg insists will not return is Ziva David (Cote de Pablo). "There'll definitely be some surprise appearances of people from our NCIS past, but Ziva David is not one of them."

Season 13 will also feature many guest stars, Glasberg shared. Jon Cryer from Two and a Half Men has been reported to make an appearance as naval surgeon Dr. Cyril Taft, the surgeon who saves Gibbs in the operating theater.

NCIS season 13 will premiere on Sept. 22 on CBS.