The NCIS team will deal with a tragedy before the season is out - but who's going to die? "It's a fan favorite, and I think it's going to be quite a shock," star Emily Wickersham, who plays Ellie Bishop, tells TVGuide.com. "It was a shock to me, and I think it will be a shock to the fans."

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The death occurs in the May 5 episode, "The Lost Boys," which is the second in a three-episode arc about a terrorist organization that recruits children online. "At the end of the penultimate episode, something pretty atrocious happens and we lose someone very close to us in the process," says showrunner Gary Glasberg, who also promises the "return of some very familiar faces that will make our fans very happy."

Of course, he may be referring to Matt Jones, who returns as Probationary Agent Ned Dorneget for at least two of the episodes. But here's another possibility: Could this mean the long-awaited return of Ziva David (Cote de Pablo)? And if it does, is it possible that she'll return to the show only to - gulp - be killed off?

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Both Glasberg and Wickersham confirm that the death in question is going to have a serious impact on the rest of the team. "It's someone that we know and that we're close to," Glasberg says. "And that will spark the appearance of other familiar faces as well." Adds Wickersham: "When there's any sort of loss of a coworker or a friend or anyone that you've known for a while, it rattles you. It becomes a motivating thing for the team."

Who do you think is going to die?

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