We're the D'Artigo sisters: savvy half-human, half-Fae agents of the Otherworld Intelligence Agency. My sister Camille is the Queen of Dusk and Twilight. Menolly is now a vampire princess. And me? I'm Delilah, a two-faced werecat and the Autumn Lord's only living Death Maiden. Even as Trytian's father maintains the Daemon front raging against him, Shadow Wing is seeking greater power by draining his own armies of their lives. His necromancer Telazhar is dead, but the Demon Lord has found a new threat to move against us, putting my fiancé, Shade, in the most dangerous situation of his life...

Shadow Wing sends Yerghan the Blade after us. The warrior led the battle alongside Telazhar during the Scorching Wars, and was banished to the Sub-Realms along with the ancient necromancer. Now, his new mission: kill my sisters and me. When Yerghan attacks my home, Shade finds himself fighting for his life. Deep in a coma, he's lost in the Realm of Wandering Souls. My sisters and I must journey there to find him and bring him back. But in order to do so, we must face our darkest fears, or forever risk losing my love among the mists of limbo.