Whispers emerge from the woods after midnight, and clocks tick backwards on All Hallow's Eve in Ravenmoor, a town lost to time and shrouded in a constant mist. It's just eerie to outsiders. However, to those who stay inside its boundaries, it is a prison based on long-forgotten sins and bloodlines. For more than two centuries, Damien Voss, the mysterious and sulky guardian of the Hollow, has roamed its afflicted territory. He was once a knight of the Obsidian Order, but after being betrayed by his own blood, he was forced to take an old vow to protect the rift between the Hollow and the world of the living, where monsters lurk beneath the darkness and forgotten souls scream. Despite being unbeatable in combat, Damien is gradually becoming less human. His soul is eroded by each blood moon, which further binds him to the evil he vowed to resist. Lena Morwyn, a weak and kind woman with shaky hands and haunting eyes, unexpectedly enters his life. Lena, who was orphaned at a young age and reared by an uncaring aunt, has spent her life escaping from visions, believing that her mind is broken. But when her estranged grandmother dies and she inherits the decrepit Morwyn estate, Lena is compelled to return to Ravenmoor—and into the heart of its secrets. She discovers an ancient grimoire encased in human skin, with pages written in a language only she understands. Her blood sung to the Hollow. Something within her stirs. Something not quite human. Damien finds himself drawn to Lena as he looks into an increase in violent spectral attacks and restless spirits. She is gentle, vulnerable, and completely unprepared for the environment she has entered, which makes her presence disturbing. However, a wave of supernatural instability occurs concurrently with her presence. And in spite of his defiance, Damien is compelled to keep her safe—not out of obligation, but out of something far more perilous: want. At the same time, the Marrow Sisters, who were killed during Ravenmoor's purge decades ago, have come back. Rising from ash and bone, they seek vengeance on the descendants of those who condemned them. But their ultimate goal is deeper: to use Lena's blood to open the portal between the Hollow and the mortal world, unleashing a deluge of ancient terrors that Damien cannot stop. Worse, Damien's erstwhile brother-in-arms and necrosorcerer, Arius Thorne, resurfaces. With charm as deadly as his magic, Arius presents Lena with a horrifying choice: accept the Hollow, become what she was intended to be, and wield power beyond imagination, or resist and die as the final pawn in a cursed bloodline. With unexpected allies, Father Malric, a half-blind priest who guards the last vestiges of the old rites, and Cinder, a smart-mouthed teen with a foot in both worlds, Lena and Damien must unravel a prophecy, confront their ancestors' sins, and battle their growing feelings for each other. But time is running short. The red moon rises in seven nights. If the gate opens, Ravenmoor will collapse. If Lena surrenders to the Hollow, she could become its queen. And if Damien dares to love her, he risks losing his soul.

Ava Thorne never felt she could be Alpha Jackson Wolfe's mate, a merciless man. She was weak and helpless, unable to match the force and domination his pack demanded. Driven by three indisputable reasons—his pack needed a strong Luna, his desire to find an alliance with another strong Alpha through marriage, and a deep-rooted dread of vulnerability—something Ava's presence brought too near to the surface—the rejection was quick and forceful. Ava departed broken and humiliated, but she left with more than just dashed dreams. She carried his secret: twin heirs to the Blood Moon Pack developing inside her. Ava comes back five years later, no more the defenseless girl she once was. She is a mother, strong in her own right but still delicate in ways that trouble Jackson. Jackson understands too late what he threw aside as foes near and treason threaten his pack. But as he finds out about his kids, old scars come back and rivals hiding in the shadows start to stir. Jackson has to choose whether he would fight for the family he unintentionally built or let darkness take over everything considering the possibility of losing everything. Ava's life is thrown back into peril; one mistake might ruin both of them. And this time Jackson could be late to rescue them.