Jackson Brodie has relocated to a quiet seaside village, in the occasional company of his recalcitrant teenage son and an aging Labrador, both at the discretion of his ex-partner, Julia. It's picturesque, but there's something darker lurking behind the scenes. Jackson's current job, gathering proof of an unfaithful husband for his suspicious wife, is fairly standard-issue, but a chance encounter with a desperate man on a crumbling cliff leads him into a sinister network --- and back across the path of his old friend, Reggie.