You can't really blame publishers for encouraging genre authors to develop their book ideas into trilogies and multipart series. There's less financial risk in publishing part four of a successful fantasy series than launching a whole new book by the author of a single successful fantasy novel. But for readers who like books to have, you know, endings, it gets wearying. Had I known Ben H. Winters's debut novel, The Last Policeman, was the first book in a trilogy, I probably never would've read it. Now that I've read the end of the series, World of Trouble, I realize that would have been a huge mistake.

The Last Policeman was a complete novel that stood perfectly well on its own. It established the world of New Hampshire detective Hank Palace, a pleasant and competent man trying to solve a murder on a planet drained of all ambition. An enormous asteroid is heading straight for Earth, and there's no way to avert the apocalypse it will bring. People stop showing up for work, they skip out on their boring lives, they stop caring about rules. It's the perfect setting for a detective novel, because even a detective as determined as Palace—one of the last few cops to stay on duty—would face plenty of unusual obstacles in his search for a missing person.

I was disheartened to learn about the existence of Countdown City, a second novel in what was now referred to as the Last Policeman Trilogy, but I read it anyway, curious to see how Winters could milk the idea into a series. (To his credit, Policeman ends with the asteroid about six months away from impact, so it's not like Winters had to retroactively change the premise—the trilogy was presumably part of the plan the whole time.) And Countdown City was an acceptable mystery, but like most second books, it didn't really end so much as set the stage for a third book.

Now that the third and final book in the series, World of Trouble, is here, I can tell you that Winters's plan works. The books make sense as a trilogy, and Trouble is a rare case where the final book improves the books that came before. Like Policeman and Countdown, Trouble follows Palace as he tries to solve a mystery. But because the book takes place in the two weeks before the announced end of the world, he's basically trying to solve a crime in a war zone. Nobody bothers to make food anymore, so everyone's hoarding. People are trying to find a comfortable place to die. No one cares about Palace's quest.

Over the course of the three books, Winters deconstructs the mystery genre and reveals it as an investigation of mortality. Why did this particular person die? Why am I going to die? Why is everyone going to die? What, in the end, does anything matter? Some evangelical Christians like to argue that a wholly atheist world would be a lawless place haunted by the inevitability of death, where actions have no consequences. Hank Palace's intrinsic decency and curiosity is a convincing argument to the contrary.