Diane Haithman is contributing to Deadline’s TCA coverage.

NCIS executive producer Gary Glasberg said after today’s TCA panel that actor Muse Watson would be among those returning to the long-running series for its 200th episode airing February 7. Watson portrays retired special agent Mike Frank, Gibbs’ (Mark Harmon) mentor. Glasberg was coy about whether other guest stars would return but confirmed that Lauren Holly will not. He said, “Just watch the show, there will be surprises.” During the panel, Glasberg elaborated on that 200th episode, “Life Before His Eyes,” which concerns a “pivotal moment that Gibbs faces” and will look back at key moments throughout the 9 years the show has been on the air. He also said the episode would bring back “familiar faces, old faces.” Glasberg and cast members including Harmon also did not say how long the show could run. Asked whether the show could run as long as Gunsmoke, Harmon joked: “I like the idea of riding a horse, if we’re gonna do that. Tomorrow we go to work.” On the 200th episode, he said: “We had a cake, and there were speeches, and we went back to work.”

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