In Coleman’s What You Break, Long Island hotel driver Gus Murphy, an ex-cop, is struggling in the aftermath of his 20-year-old son’s death.

Why did you decide to make Gus a hotel driver?

I drove a home-heating oil-delivery truck for seven years, and I noticed that I was invisible to the people to whom I delivered oil. I love the notion of jobs where people who do them are invisible to others. For Gus, it’s the perfect job because it’s mindless, and he doesn’t have to form emotional attachments. It’s a metaphor for his life after his son’s death.

What does the Suffolk County setting add?

People think they know Long Island, but what they know is the Gold Coast or the Hamptons, Gatsby, the golf courses, the yachts and the mansions. But that’s not the Long Island I live in or on. When I delivered oil, I had customers who were so poor they often had to choose between food and heat. Yes, we have the Hamptons and wine country, but for many of the people here those places might just as well be on Mars. I wanted readers to see the Suffolk County those people live in, its good and its bad, its beauty and its ugliness.

Do your books share any themes?

I suppose all my novels, series or standalones, share at least two essential themes. You can never truly know someone else because it’s impossible to know yourself. And that violence sends echoes through time and reverberates in the future. As I once wrote in a Moe Prager novel, there are victims of the Holocaust yet to be born.

How has the market changed for PI fiction from when you began writing?

I try very hard not to occupy myself with worries about the marketplace. It’s difficult enough to produce 100,000 words twice a year without these added concerns. That said, I’m not blind. At the moment, PI fiction isn’t very popular. At the beginning, PI fiction was the big tree in a small orchard. Now it’s just one of the trees in a big orchard, and some of the fruit is going unpicked or rotting on the limbs. There’s some great PI stuff out there, but there doesn’t seem to be a vast yearning for it. Yet I’m very hopeful. I think PI fiction surges when we have worries about our political system. The PI is symbolic of the one against the many, the solitary citizen against the state and the system. The PI is the redeemer, the person who sets the universe back on course. We’ll see.