Towering live oaks guard old secrets and powerful forces that even the spirited Bay Tanner can't control. . . . A freak summer storm has Bay Tanner, sometime private investigator, cooped up with her ailing father at his antebellum mansion near Hilton Head. Desperate for a distraction, Bay recovers a cooler bobbing along on the incoming tide. What she discovers inside will plunge her into a world of ancient magic where the power of the "root" has held sway since the days of the slave row. Suddenly, mysterious people and strange incidents, including a near-fatal accident, force her to realize that she may have unleashed something she can neither understand nor escape.
Meanwhile, her investigation into the simple case of a runaway wife turns deadly. The police are eager to nail the wealthy, prominent husband for murder, but Bay's instincts tell her there's more to the story. Sheriff's Sergeant Red Tanner, her late husband's brother, warns her off the case, but Bay's never been good at taking orders. Soon she's working full-time to defend her client, who may not be as innocent as Bay would like to believe.
Time and again, every trail leads back to a mystical commune in the tangled backwoods of Beaufort County and to one of its leaders, a charismatic woman who believes in the real and malevolent power of the old ways. To find a killer, Bay must travel to the heart of this woman's world--and not everyone will escape the spell of Sanctuary Hill.