What would it take for Tony DiNozzo (Michael Weatherly) to leave NCIS?

Fans will find out on the upcoming Season 13 finale of NCIS, titled "Family First," which airs May 17 and will be Weatherly's final episode on the show.

"This is a story line that we've literally been working on for six months, and that includes working with Michael," NCIS showrunner Gary Glasberg, who co-wrote the episode with executive producer Scott Williams, tells TVGuide.com. "The whole writing staff has participated in this story line. We 100 percent want to deliver an episode that satisfies the audience, that emotionally takes them on a roller-coaster ride that hopefully will resonate with them for a long time to come."

NCIS: Will Cote de Pablo return for Tony's send-off?

The May 10 episode finds the NCIS crew continuing their manhunt for the escaped British spy who (presumably) shot Morrow (Alan Dale) in this week's episode, and who leaves one NCIS colleague fighting for his/her life in the penultimate installment. Could the person on life support be Tony? Glasberg won't say, but when asked if Tony's decision to leave NCIS is one that he makes on his own or is forced into, the executive producer notes: "It's a little bit of everything. There are outside influences. There are issues that come up. There are crossroads that he faces. It's, across the board, something that has a mammoth impact on him -- and understandably, would take that significant an impact to have him step away from his NCIS family."

Of course, the big question on everyone's minds is whether Ziva David (Cote de Pablo) will play a role in Tony's exit. "Tony's relationship with Ziva certainly will have an impact on his reason to depart NCIS -- but just like his relationship to McGee or to Gibbs or to anybody [will]," Glasberg demurs. "In terms of who he is as a character, is she a part of who he is? Absolutely."

One thing that's a near-guarantee, however, is that producers have no intention of killing off Tony. "We acknowledge the importance of this episode," Glasberg says. "Michael's been a part of this show since Day 1. So we're very eager to deliver something that we hope gives people everything they want from his exit."

NCIS airs Tuesdays at 8/7c on CBS.

(Full disclosure: TVGuide.com is owned by CBS.)