Preeminent New York psychiatrist Dr. Nathan Conrad has a successful Upper West Side practice, a beautiful wife and a charming daughter. Making his way home to begin a tranquil Thanksgiving holiday, Conrad is summoned by a colleague to examine a young woman, Elisabeth Burrows, who presents a history of unexplained violence and a miasma of failed treatments and misdiagnoses. Nathan's skills and intuition make headway into Elisabeth's case, and his curiosity is aroused by her mysterious first words to him: "You want what they want, don't you? ... I'll never tell ... any of you."
Little does Nathan suspect that Elisabeth and her cryptic message are tied to a danger that has closed in on him and his family. Nathan's daughter has been kidnapped by ruthless thieves, and to save her, he somehow must unlock a six-digit number locked away in Elisabeth's troubled mind. Nathan is trapped in a nightmare even he could never have envisioned. And as Nathan is reminded constantly by his tormentors: if he wants to see his daughter alive, he dare not say a single word.