Katherine (Famke Janssen), a former television star, wakes up in the hospital after a serious accident that has left her with locked-in syndrome, a condition in which she is completely paralyzed and unable to communicate. A nurse named Nicky (Anna Friel) begins working with Katherine to help her regain bodily control. Nicky seeks information about Katherine from Lina (Rose Williams), the wife of Katherine's late stepson, Jamie. Through a series of flashbacks, we discover the events leading up to the accident and unravel a plot of betrayal, jealousy, and murder.