This one-hour ET special gives fans a behind-the-scenes look at the franchise's 1,000th episode and includes exclusive interviews with the stars of NCIS, NCIS: LOS ANGELES, NCIS: NEW ORLEANS, NCIS: HAWAI'I and NCIS: SYDNEY. The cast and guest stars share favorite memories and behind-the-scenes moments from 20 years' worth of never-before-seen interviews from the ET vault.