Then one night, when she comes face to face with Matthew in a dark parking lot, she realizes that he knows she's been watching him, that she's really on to him. Could her neighbor, Matthew, be a killer? Or is this the beginning of another psychotic episode like the one she suffered back in college, when she became so consumed with proving a fellow student guilty that she ended up hurting a classmate? The more Hen observes Matthew, the more she suspects he's planning something truly terrifying.

Hen knows because she's long had a fascination with this unsolved murder-an obsession she doesn't talk about anymore, but can't fully shake either.

The sports trophy looks exactly like one that went missing from the home of a young man who was killed two years ago. But when they meet the neighbors next door, that calm begins to erode as she spots a familiar object displayed on the husband's office shelf. Finally, she's found some stability and peace. Hen (short for Henrietta) is an illustrator and works out of a studio nearby, and has found the right meds to control her bipolar disorder.

Hen and her husband Lloyd have settled into a quiet life in a new house outside of Boston, Massachusetts. Catching a killer is dangerous-especially if he lives next door From the hugely talented author of The Kind Worth Killing comes an exquisitely chilling tale of a young suburban wife with a history of psychological instability whose fears about her new neighbor could lead them both to murder.

Book before she knew him