ET's Kevin Frazier hops on board and visits the set of "NCIS" to help solve the mystery surrounding the death of a Marine who lived a double life. Are either of the man's two wives connected with his death?
Mark Harmon (Special Agent Jethro Gibbs) explained that both wives showed up once the Marine was found dead. "There's a lot of different issues here and a lot of different stories and different directions and, as always here, at the end it's not what you thought it was going to be at the beginning," Harmon teased with suspense.

ET correspondent and "NCIS" supporter Kevin Frazier shared some laughs with the CBS cast as they partied at the Paley Festival -- but the question of the night was: Where was actress Pauley Perrette (Abby Sciuto)?
Perrette was in France doing promotions for the program but Michael Weatherly (Special Agent Anthony DiNozzo) kept her presence alive, showing up to the event with a cardboard cut-out of his costar. "We have a facsimile of Pauley. Ask her any question and she's free to answer," Weatherly joked. "If Mark Harmon sees me with a cutout of Pauley, I'm going to get a fat lip."