Outside London behind a stone wall stands Lake House, a private asylum for genteel women of a delicate nature. In the winter of 1859, recently-married Anna Palmer becomes its newest arrival, tricked by her husband into leaving her home, incarcerated against her will and declared hysterical and unhinged. With no doubts as to her sanity, Anna is convinced that she will be released as soon as she can tell her story. But Anna quickly learns that liberty will not come easily. And the longer she remains at Lake House, the more she realises that - like the ethereal bridge over the asylum's lake - nothing is as it appears. She begins to experience strange visions and memories that may lead her to the truth about her past, herself, and to freedom - or lead her so far into the recesses of her mind that she may never escape.