From the author of The Five Year Lie comes a new twisty thriller that probes how well we actually know the men in our lives.

Rowan Gallagher is a devoted single mother and a talented architect with a high-profile commission restoring an historic mansion for the most powerful family in Maine. But inside, she's a mess. She knows that stalking her ex's avatar all over Portland on her phone isn't the healthiest way to heal from their breakup. But she's out of ice cream and she's sick of romcoms.

Watching his every move is both fascinating and infuriating. He's dining out while she's wallowing on the couch. The last straw comes when he parks in their favorite spot on the waterfront. In a weak moment, she leashes the dog and sets off to see who else is in his car.

Instead of catching her ex in a kiss, Rowan becomes the first witness to his murder-and the primary suspect.

But Rowan isn't the only one keeping secrets. As she digs for the truth, she discovers the dead man was stalking her too, gathering intimate details about her job and her past.

Struggling to clear her name, Rowan finds herself spiraling into the shadowy plot that killed him.

Will she be the next to die?