Frank (Dan Stevens), Sammy (Kathryn Newton), Peter (Kevin Durand) and Joey (Melissa Barrera) are a group of would-be criminals. When they kidnap Abigail (Alisha Weir), the 12-year-old ballerina daughter of Kristof Lazar (Matthew Goode), a powerful underworld figure, all they have to do to collect a $50 million ransom is watch the girl overnight.

As they keep her captive behind bars in an isolated mansion, the kidnappers start to dwindle, one by one, as they discover, to their mounting horror, that they're locked inside with no normal little girl.