Heiress Elena is poisoned by her fiancé Justin and stepsister Lilith at her engagement banquet and pushed off a cliff into the forbidden black forest. At death's door she is saved by Alexander, the wolf king of the Black Moon wolf clan, and signs a contract to gain revenge power. Elena follows the wolf king to learn self-defense, and love-hate bonds grow amid their tug-of-war. She returns to the human city and reclaims her group's industry step by step. Meanwhile, the ambitious conservative elder Victor of the wolf clan colludes with the fallen Justin and Lilith, planning to assassinate her when the moon's power wanes. Elena and Alexander join hands to settle the betrayers and face the internal rebellion, writing a tragic love legend spanning the human and wolf clans through trials of power and life and death.