Arden, undercover for The Wardens of the Realm who protect 1898 steampunk England, has the status, wealth, and independence of a countess - and can see the final moments of a murder victim’s life. Her husband Lucas vanishes until she spots him one night. The Company wiped his memory, sent him to kill her, but he cannot. Yet if he does not, someone will—and kill him.

The Wardens of the Realm are a group with extraordinary abilities, dedicated to protecting England from any threat. But in this steam-powered world, there’s a fine line between enemy and ally… Reeling from her brother’s death, beautiful American spy Claire Brooks has vowed revenge on the member of The Company who she believes to be responsible: Stanton Howard. But when she chases the man to London, Claire is captured by the Wardens of the Realm and placed in the custody of the Earl of Wolfred, the dashing Alistair Payne. Seeing the prospect of retribution slipping away, Claire convinces Alistair that she has defected and will help him take down The Company. As they travel via steam liner, Claire and Alistair must pretend to be engaged. Claire can’t deny the growing attraction she feels for her pretend husband, but when Howard is finally within her reach, she will have to decide whether her true loyalties lie with The Company or with her heart…

Sworn to protect England from all enemies, the Wardens of the Realm are ever vigilant. But not all battles are fought on a battlefield; sometimes they are fought in the heart. As chief surgeon for the Wardens, Evelyn Stone fears her own life is on the line when she is kidnapped by a band of pirates—only to discover that the airship captain is Gavin “Mac” MacRae—her former lover. The man whose life she once saved. The man she abandoned. Since Evelyn left, Mac made his mark as both a pirate and a pilot. But his true allegiance isn’t known. Upon asking Evie for help with a wounded woman on board, he tells Evie that the woman is his wife—even though his feelings for Evie have never waned. As the days pass, however, the unease between Evie and Mac gives way to the old comfort they once had. Yet, their newly ignited romance is complicated by conflicting loyalties and desires, and a betrayal that may cost both of them their love and their lives.