In 2020, sixteen-year-old Elizabeth lives peacefully with her father Sebastian and her stepmother Grace—until anonymous messages warn that their family is "surrounded by enemies." When a dinner guest is mysteriously poisoned, Elizabeth is accused and thrown into a nightmare of suspicion and betrayal. Her only ally is Arthur, the son of her father's closest friend, who risks everything to prove her innocence.

As Arthur digs deeper, he uncovers a horrifying truth: Grace and his own father Harry have conspired for years, driven by greed and a pact with a sorcerer who promised them a hidden treasure. The bargain awakened Qutrub, a demon demanding a human soul—the "treasure girl" born under the cursed year 2020.

Sebastian's death, Grace's descent into madness, and Harry's guilt tear the families apart. Yet from the ruins of deceit and darkness, love endures. Arthur and Elizabeth rise from tragedy to face the curse that destroyed their world, proving that even in the shadow of betrayal, light can return.