Brothers Lee and Andrew Child collaborate on their second Jack Reacher thriller, Better Off Dead (Delacorte, Oct.).

Lee, how do you divide the writing responsibilities?

Lee Child: Andrew does all the actual work. All I do is think along with him, while we’re both thinking along with Reacher, and occasionally I say something that breaks a logjam, or Andrew refers back to a line in a previous book, and I’ll remember the thinking behind it, which might lead to a random new direction. His characters are subtle—I think that’s the take-away from the series he’s done before. Writing is a total joy, but it’s also a hard job, and right now I’m getting all of the good and none of the bad, and Andrew’s getting all of the bad and, I hope, some of the good. But hey, I’m the big brother.

Andrew, is continuing the series easier or harder than writing your original novels?

Andrew Child: I would have to say it’s harder. Not because of adopting someone else’s character. Not because of having to think up suitable plots or similar action sequences. But because of style. I spent 13 years learning how not to sound like my brother when I write, so having to pull a complete about-face and suddenly produce sentences that even our editors can’t tell apart was one of the biggest challenges I faced.

Lee, will there come a point where only Andrew is writing Reacher?

I think so, and I hope so. Like I’ve said, everything I know comes from the reader side of my brain, and readers don’t really care about authors or publishers or anything except the character. The name James Bond is a thousand times better known than Ian Fleming. That was my instinctive strategy from the start—I didn’t want people ducking into bookstores and asking, “You got Better Off Dead yet?” Or, “You got the new Lee Child yet?” I wanted them to ask, “You got the new Reacher yet?” And, by a massive majority, they have. So as long as Reacher is Reacher everyone will be happy. And he’ll be in seriously good hands with Andrew. He’s a great writer. He’s got the voice. And if I grew up with Reacher, so did he.

Andrew, in what ways are these two books reboots of the solo-written series?

I don’t see them as reboots. To me, it’s more like we’re runners in a relay race at the point where the baton is passed from one to the other. The objective is the same. The method is the same. It was just time for a fresh pair of legs.