Inspired by true events, the film follows the story of Sarah Winchester, a woman who, after the sudden death of her husband and child, becomes convinced she is cursed and starts building the Winchester Mystery House in San Jose, California after consulting with a medium. Built in twenty-four hours a day, seven days a week for decades, the house has seven floors high and contains hundreds of rooms. For outsiders, it looks like a monstrous monument to the madness of a troubled woman. But Sarah does not build for herself, for her niece or the brilliant Doctor Eric Price whom she has invited to the house. It builds a prison, an asylum for hundreds of venomous ghosts, and the most frightening of them has an old problem with Winchester.