Twenty years ago, Susan Lentigo lost her only daughter, Amy. And from now on, all she wants is to achieve justice. The woman is planning a trip to North Dakota to execute the Beast. Maybe after that she will finally be able to let go of the past, finish her work with a psychiatrist and "move on". On her way to North Dakota, a woman stops by to visit a loved one and comes across a key piece of evidence involving a colorful necklace that looks like her daughter's. Susan demands a review of the case, but the FBI considers her a neurasthenic. To save two lives and put the real Monster behind bars, Susan decides to do her own investigation. But will she succeed? And did the found necklace really belong to Amy?