Novelist Carla Buckley was at a turning point in her career when she started to work on her third novel. "I had signed a two book contract with Random House and this was a make or break time for me," Buckley tells us. "Was I going to be a career novelist? Or was I going to be a writer who got a lucky break and then never got anything else published? I was frantic trying to figure out what I wanted to do next."

Buckley settled on The Deepest Secret, a family drama about a mother and her teenage son. "To push that relationship into high [gear], I wanted to throw something in that they could both be struggling with." She choose to give the son a disease and searched for more than a year for the perfect ailment. In the end she chose xeroderma pigmentosum, an extreme sensitivity to light.

"I explored a number of illnesses and then I found this one. The moment I stumbled on this one, I knew it was the one I wanted to use. Everything fell into place. Once I knew what disease I was going to be talking about, I could see those characters and what they were facing, what was pushing them together and then pushing them apart."

Buckley wrote the first draft, but wasn't happy. "It was a pretty traditional mystery and it didn't let the reader in until the very end. The result was that there was no suspense and my characters were completely unlikeable. When I went back and redid it and took the reader along with me, it was a big change. Looking back, I think that made the difference. This book was really a game changer. This was really the first time that I stepped back and let the story tell itself."

In The Deepest Secret, the mother has made her son her main priority. She's on constant vigil for his safety and she shapes her life around his needs. When she's faced with the decision to sacrifice her best friend's daughter in order to keep her son safe, she makes what some readers will think is the wrong choice.

There are no heroes in Deepest Secret, Buckley says. There are no good guys, no bad guys according to her. "What I try to do is show people as people, not your stereotypical bad guy, not driven by the terrible motivations of greed and selfishness. Everybody is doing the best they can given the circumstances, and that sometimes makes them do unlikable things. My hope is that the reader, even if they don't agree with what my characters are doing, can understand them. I always have my characters, with the best of intentions, make the worst of choices. Isn't that how people are?"

"I always hear from my readers that they either love or hate my characters. For me that's pretty exciting because it means they care, they're invested enough to actually form an opinion and make a judgment. That's exciting."

Carla Buckley reads from and signs The Deepest Secret at 6:30 p.m. on February 11. Murder by the Book, 2342 Bissonnet. For information, call 713-524-8597 or visit murderbooks.com. Free.