Tuesday's episode of Person of Interest will feature the return of a familiar face: Taraji P. Henson's Detective Carter.

The episode features the actress, who now stars on Fox's Empire, in flashbacks as Reese (Jim Caviezel) tries to solve a cold-case murder Carter was never able to close. Although the episode will likely be treat for those viewers who have missed the character since she was killed off in Season 3, executive producer Jonathan Nolan said the show has always intended to bring the character back into the mix.

Mega Buzz: Who's coming back to Person of Interest?

"We had always said... that everyone lives forever in flashback on Person of Interest," Nolan said during a Person of Interest panel, moderated by this reporter, at the Paley Center in New York Monday. "We were very, very sorry to see her go and from the very beginning had been cooking up a way to get Cookie back on our show."

But Henson's return was a surprise for the cast. "They're amazing at keeping secrets," Caviezel said. "I had no idea Taraji was coming until literally like 20 hours or 30 hours before."Below, you can watch the entire panel, which also features cast members Michael Emerson, Amy Acker and Kevin Chapman, and executive producer Greg Plagemandiscussing this season, the show's future and the bloody season finale.

Person of Interest airs Tuesday at 10/9c on CBS.

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