At the end of its second year, a fairly new Navy-based procedural spinoff of hit show JAG did something shocking. So shocking that it still seems to shock audiences nearly 20 years after it happened. With absolutely no dramatic lead up, NCIS killed off one of its core characters, Caitlin 'Kate' Todd.

And they did it by having her shot in the head in the very last few moments of an episode.

So yeah, shocking. But how did the show keep the secret in the bottle? It takes a whole lot of people to make a television show, and loose lips sink ships (as does a script accidentally forgotten in a bathroom somewhere). Obviously, the smart minds behind one of the now longest-running shows in TV history had some ideas.

How did NCIS keep the secret of Kate's death?

In an oral history about NCIS published by The Hollywood Reporter, executive producer Mark Horowitz shared about how NCIS was able to keep this huge plot twist from leaking. For one, they only printed a single script page of Kate being shot. That meant that the actors and crew involved in the scene would have to read that page in person and then return it.

Not only that, the actual physical bit of film holding that huge plot twist was "broken off from the rest of the film shot for that day." If that bit of spycraft seems overkill, the NCIS team added a third failsafe - they filmed a false ending. The whole charade worked so well that, according to Horowitz, "Even my wife didn't know."

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