Lisa Unger, 43, has always been drawn to places that seem idyllic yet seethe with hidden treachery. “The dichotomy of a place fascinates me—that glittery, peaceful shell that gives way to something quite different below,” says Unger. “There is so much to explore in those two sides—what a place sells itself as and then the real place that you don’t see right away.”

That fascination may be one reason why Unger keeps returning to the Hollows, the fictional upstate New York town she introduced in Fragile (Crown, 2010). Her latest novel, In the Blood (Touchstone, Jan.), explores a young woman’s violent tendencies, which she may have inherited. It’s Unger’s third book set in the Hollows, and it features recurring characters such as Jones Cooper, a cop turned private detective, and his wife, Maggie, a psychologist, both of whom play minor but pivotal roles in the story. “In Fragile,” Unger says, “Jones was just going to be ‘the husband.’ But he has become very important. He probably deserves his own book.”

When she first created the Hollows, Unger says, she thought it “would just be a place, just somewhere [Fragile] was set; I didn’t expect it to have such a hold on me.” She adds, “It has evolved into a real character. The Hollows is not a malicious place but it definitely has an agenda. It doesn’t like secrets, and it encourages paths to cross.”

And the Hollows does have a personal resonance. When Unger was about 15 years old, a teenage girl she knew was abducted and murdered by a man in the New Jersey town where she lived (today she lives in Clearwater, Fla., with her husband, Jeff, and their seven-year-old daughter, Ocean). The incident inspired Fragile. “It was a shocking tragedy. Nothing had ever happened in that town, and then the worst thing that could happen did,” says Unger.

In the Blood marks the culmination of a two-year career transition for Unger—a transition, she says, that reflects the changes in the publishing industry. Unger has a new publisher: In the Blood is her first book with Simon & Schuster, part of a two-book deal with Touchstone editorial director Sally Kim. “All of the changes were motivated by positive factors, not negative ones,” she says, adding that her backlist is still being published by Crown. The move to Simon & Schuster puts Unger back in contact with Liz Perl and Louis Burke; both were her former bosses at Penguin Putnam, where she worked as a publicist for 10 years. “Publishing is a business of relationships,” says Unger. “The relationships you make at one house can carry over to another.”

Originally, Unger planned to relaunch her series about magazine writer Ridley Jones, introduced in Beautiful Lies (Shaye Areheart, 2006), for Simon & Schuster. “Ridley is still percolating—she has been on my mind for many years,” says the author. “I thought her story was done, but a lot of unanswered questions about Ridley’s life have stayed with me.”

Now Ridley is on hold for at least two years. In the Blood will be followed by another visit to the Hollows in 2015, in a novel Unger will describe only as “the biggest evolution yet for the town.” In addition, she is writing her first YA series, the Dark Doorway Trilogy, about 16-year-old Amelia Strange. The first of these YA fantasy novels will come out in 2015 under the Simon & Schuster Books for Young Readers imprint. Unger is still working on the first book, but she already has one reader riveted—her daughter. “Each night, Ocean asks me what happened to Amelia today,” says Unger. “She keeps me writing every day.”

Ocean may be getting a preview of the trilogy, but Unger says her daughter is still too young to read the series, which she expects will get darker with each novel. While Unger says she “doesn’t shy away from violence,” she prefers to explore psychological rage. “The worst violence we can do to each other often is psychological, especially in families. I dwell a lot on domestic danger. That’s the backdrop of most of my novels—what kind of damage is done without ever lifting a finger.”

Being an author has been Unger’s dream since she was a child; she says that at college and while working at Putnam, she was a “closet writer,” fleshing out the character who would be Lydia Strong, the heroine of Angel Fire (Minotaur, 2002), the first of four novels published under her maiden name, Lisa Miscione.

Unger says her childhood helped shape her desires to be a writer. She was born in Connecticut, but her father’s job with Exxon required the family to frequently move—to the Netherlands, England, New Jersey, and New York. “I was always on the margin of things, and that is really where a writer should be. If you are in it too deep, then you are not an effective observer,” she says. “I was always the observer, trying to understand what was going on. I was always the new kid. Writing became my safe place.”

“Maybe I have this fascination with the dark side because I live in the light,” says Unger, whose imagination seems at odds with her gregarious personality. “I don’t have any dysfunction, and I’ve never experienced trauma. I have a good [family] and I am a happy person. But in my heart, I am the girl in the horror movie who is walking down in the basement to find out what the sound was. I spend a lot of time digging under the surface to find what is really there, what is really going on with people.”