Based on a true event, an incredible tale of a woman locked up in a psychiatric ward against her will and a daughter who refuses to give up searching for her.

When Mattie McAllister was eight years old, her father told her that her mother, Heather, had died while a patient at Milledgeville asylum. A father wouldn't lie about such a thing, or would he?

Mattie and her brother are put into foster care by their uncaring father and manage to survive until rescued by their Aunt Tess. After Mattie completes her degree in nursing, she decides to take a job as a psychiatric nurse on the new crisis stabilization unit at Milledgeville asylum, the place where she believes her mother died. She meets an assortment of unlikely characters hired to work on the new unit: an erratic supervisor, a cute ex-Dominican monk, and a beautiful clinical social worker who has terrible luck with men.

At the same time Mattie is adjusting to her new job, Heather is living on Ward A, the worst regressed women's ward in the entire hospital. She sleeps in a dorm along with ninety other women, most of whom are psychotic. She does have one good friend, Lucinda, also completely sane, and their friendship keeps Heather grounded during the most trying of circumstances.

Mattie had been told her mother died at Milledgeville, but she has always wondered what caused her death. Did she have a rare genetic illness? or perhaps she had an accident? Tuberculosis was rampant in the hospital in 1958, the year her mother was admitted. Did she succumb to it?

When Mattie learns there are old ledgers in the hospital library, she visits the library and pores over them until she finds Heather's name. She is astonished to discover her mother had not been classified as dead, and was never discharged-no, she is very much alive But what ever has happened to her? Where can she be? All traces of her have disappeared. There are more than 12,000 patients in the mammoth hospital. The search is on

What Ever Happened to Heather looks at the heartbreak caused by mental illness, the value of women's friendships, and the long-term effects of grief and loss-and there is a reminder that for every wrongdoing, every act causing another person suffering or misfortune, karma is patiently waiting, right around the corner.