After discovering her boss's dead body, Susanna Trent receives an unusual package from him filled with strange metal tokens and odd clues. Then Susanna, who is the guardian of her three-year-old niece, starts getting anonymous phone calls taunting her with thinly veiled threats. Worried for her life and that of her sister's child, Susanna struggles to trust the one man who can help: wealthy executive Jack Townsend. As they work together to solve the mysterious puzzle, Jack and Susanna are led into a dangerous game neither knows how to play. But they do know the stakes—life or death.