Lady Kiera Darby and her dashing husband, Sebastian Gage, hope they've finally found peace after a tumultuous summer, but long-buried family secrets soon threaten to unravel their lives . . .

October 1832. Kiera is enjoying the slower pace of the English countryside. She, Sebastian, and their infant daughter have accompanied her father-in-law, Lord Gage, home so that he can recuperate from the injuries he sustained in a foiled attempt on his life. But as the chill of autumn sweeps across the land, they receive a summons from an unexpected quarter. Lord Gage's estranged uncle—a member of the notorious Roscarrock family—has been murdered, and his family is desperate for answers. Despite Lord Gage's protests, Kiera and Sebastian press on to Cornwall to assist.

It isn't long before they discover that almost nothing is as it seems among the Roscarrocks, and they've been lured to their isolated cove under false pretenses. There are whispers of a lost treasure and frightening allusions to a series of murders stretching back decades that touch the lives of the family personally. Kiera and Sebastian are left with no choice but to uncover the truth before the secrets of the past threaten to destroy them all.

June 1920, Ireland: The streets of Dublin seethe with revolution as the Irish Republican Army clashes with British authorities. Roving assassination squads mean nowhere is truly safe, particularly for Verity Kent and her war hero husband, Sidney. Given their celebrity as society darlings and intrepid sleuths, they must tread carefully to go unnoticed—nearly impossible when they are called upon to search for Verity's fellow spy and friend . . .

Captain Alec Xavier has seemingly vanished after traveling to Dublin to infiltrate the IRA at its highest levels. Doing her best to maintain a modicum of normalcy and stay under the radar of both the rebels and British Intelligence, Verity works undercover by day and waltzes through the city's elite social scene by night. Still, she fears the worst for Alec—until shocking evidence mounts that not only is he alive, but that he has switched sides . . .

Already disillusioned with the British government, the news leaves Verity and Sidney reeling. Worse, they learn of a conspiracy within Dublin Castle, where personal vendettas are being carried out and sanctioned by British Intelligence under the cover of revolution. With the distinction between friend and foe never more blurred—or the margin for error narrower—Verity and Sidney cannot turn a blind eye. Especially when a familiar adversary appears, bringing a threat almost too terrifying to confront—even in the cold light of day . . .