To save her dying younger brother, Alice is forced to become the bride of Cain, a Vampire Prince. Within the shadowy Nightfort Castle, she gradually falls for the lonely masked prince. After conceiving his child, she discovers a portrait hidden in a secret chamber — the woman in the painting shares her exact face.
Convinced she is merely a substitute for his former lover Cecilia, she flees the castle on a snowy night.
Alice gives birth to their son Kay alone in a forest cabin and lives under an assumed name for six years, leaving Cain searching endlessly for her. On Kay’s sixth birthday during the Blood Moon, the boy’s vampire blood awakens, unleashing world-shaking power. At last, Cain tracks them down, yet Alice turns him away.
Meanwhile, villains stage a coup and abduct Alice and the child, driving Cain into a blood-frenzied rage. He nearly slays Alice, who cries out in despair that all bonds between them are broken. Cain is captured, nailed deep inside the dungeon to await his end.
The elderly steward finally reveals the truth: Alice is Cecilia’s reincarnation, the person Cain has waited three hundred years for. Alice rushes to the dungeon and breaks the curse with her blood. Just as the villain strikes to kill them, she seals her love with a true love’s kiss. The ancient curse shatters, and Cain’s true appearance is restored.
He defeats the usurpers and rescues their son. The family is reunited. The old portrait is replaced, and sunlight floods the castle.
