When Gina Higgins drives her beat-up old car into Kiss River, a small town on the Outer Banks of North Carolina, she arrives as a stranger determined to expose long-held secrets in the close-knit community. But she comes with secrets of her own, and a hidden agenda she is resolved to keep to herself.
She poses as a historian researching the town's famous lighthouse that has all but fallen into the sea, taking with it the huge Fresnel lens that once served as its beacon. In reality her interest in the fallen relic is more than just academic - it represents a vital piece of the puzzle she has come to Kiss River to solve.
Gina wants to discover the truth about her grandfather, a local man she believes was a spy during WWII and who she suspects made millions of dollars working for the Germans. She believes the lighthouse lens holds the answers to her questions, and is desperate to find a way to raise the lens from the ocean depths.
She is met with firm resistance from most of the locals, and drawn into the struggle is Clay O'Neill, a young widower who lives in the old lightkeeper's house. As Clay and Gina search for the truth, an old diary that belonged to Gina's long-lost grandmother reveals the shocking legacy of a girl swept away by love and plunged into the treacherous waters of WWII espionage.