By Oline H. Cogdill
Sun Sentinel (MCT)

The One I Left Behind
By Jennifer McMahon
Wm. Morrow, $14.99

Jennifer McMahon’s novels share a common link — expert plotting complemented with a real feel for the complicated nature of relationships, feelings and what motivates a person’s actions.

The Vermont-based author continues that high standard in her fifth novel. “The One I Left Behind” works well as a mesmerizing psychological thriller, as a look at how childhood trauma can forever scar an adult and as a testament to the power of the past and how people can hold sway over others. And just for good measure, McMahon throws in a bit of small-town angst and a touch of the gothic to make the story even more fascinating.

Reggie Dufrane knew what it means to feel like an outsider, to feel inadequate, awkward and angst ridden. A gangly child, she lived with her distant aunt and her glamorous mother, Vera, a former model and actress, in a rambling house. Reggie’s only friends were other outcasts, the goth girl, Tara, forever blamed for her parents’ divorce, and Charlie, the police chief’s sensitive son.

When she was 13, a serial killer called Neptune murdered four women in her small town of Brighton Falls, Conn. Vera was believed to be the last victim, although her mother’s body was never found. Now 39, Reggie has reinvented herself as one of the top “green” architects in the country, a sought-after professional with a lucrative career and multiple awards. She never discusses her past until her aunt calls to tell her that her mother has been found living in a homeless shelter, dying of cancer and incoherent.

Reggie’s return home is fraught with emotional peril. Her mother, who had been mutilated by Neptune, won’t, or can’t, say where she has been. The rambling house where her mother has been living is now just spooky. She and her childhood friends have gone in different directions. But worst of all, Neptune appears to have followed Vera back home.

To save her mother — and herself —Reggie begins to look into her mother’s past and learns Vera had a secret life of “too many boyfriends” and “too much gin.”

McMahon expertly shifts the time from the present to Reggie’s childhood to explore the girl who became a woman, showing her vulnerability and her strong will. Subtly, McMahon shows how Reggie’s demand for perfection in her work is diametrically opposed to the chaos in her life. Her penchant for “blurring the lines” serves her architecture well, but makes for messy relationships. Reggie has not been able to break that tight rein of the past and Vera’s disappearance.

McMahon fills “The One I Left Behind” with unpredictable twists and turns as she explores that great mystery of the human heart.