In scenic Granite Harbor, life has continued on―quiet and serene―for decades. That is until a local teenager is found brutally murdered in the Settlement, the town's historic archaeological site. Alex Brangwen, adjusting to life as a single father with a failed career as a novelist, is the town's sole detective. This is his first murder case and, as both a parent and detective, Alex knows the people of Granite Harbor are looking to him to catch the killer and temper the fear that has descended over the town.

Isabel, a single mother attempting to support her family while healing from her own demons, finds herself in the middle of the case when she begins working at the Settlement. Her son, Ethan, and Alex's daughter, Sophie, were best friends with the victim. When a second body is found, both parents are terrified that their child may be next. As Alex and Isabel race to find the killer in their midst, the town's secrets―past and present―begin bubbling to the surface, threatening to unravel the tight-knit community.

At once a page-turning thriller and a captivating portrait of the social fabric of a small town, Granite Harbor evokes the atmosphere of HBO's Mare of Easttown with a villain reminiscent of Thomas Harris's Silence of the Lambs.