When "NCIS" debuted in 2003 (as a spinoff of "Jag"), no one could've predicted it would become one of the most successful franchises on television. Sure, it had a shot at longevity being a law enforcement procedural at a network, CBS, that knew how to develop them (as evidenced from their expanding "CSI" brand). But a series that lasted 23 seasons (and counting) while spawning six spinoffs (to date)? Not even series creators Donald P. Bellisario and Don McGill could've seen this coming.

22 years later, the "NCIS" franchise is on the cusp of introducing what might be its most highly anticipated new series thus far. Even if you're only a casual "NCIS" fan, you know all about Senior Field Agent Tony Dinozzo and Special Agent Ziva David. As portrayed by Michael Weatherly and Cote de Pablo, the "NCIS" duo, called "Tiva" by fans, struck up a flirtatious working relationship which, in classic television will-they-or-won't-they fashion,...