Nathan Fillion

The Castle star, 47, returns to ABC in The Rookie (Oct. 16) as John Nolan, who becomes the oldest newbie on the LAPD force—and has to convince his fellow officers he’s not just a walking midlife crisis who could be putting lives at risk.

What’s your take on starting over, like John Nolan does? I think it’s the new norm. Our society is evershifting and things change so rapidly, you have to be able to change along with it.

What does John bring to his job that a 20-year-old doesn’t? Experience. And in a lot of ways, that helps him. In a couple of ways, that does him a disservice. He’s accustomed to a life where everything operates well within the realm of reason, but as soon as somebody’s dialing 911, things are operating outside that realm.

How are you handling the physical part of playing a cop? When the new Mission: Impossible came out, there was a lot of press about how many of the stunts Tom Cruise did. However, for me, just kneeling down is a stunt.

Castle had a sense of humor. Will there be humor in The Rookie? Absolutely, but the humor will be more reality based. [Richard] Castle enjoyed spinning a yarn; John Nolan is a reality-based guy.

How do you remember your time on Castle? Fondly. I made a lot of great friends on that show. I remember I walked into an audition and there were five guys in the waiting room and all of them had been on Castle. That’s a neat experience.