Jean has been trapped in her room for 13 years. Her life is dominated by bizarre rituals; she washes her hands 50 times a day and is compelled to check constantly the position of every item of her furniture. Jean's husband Ian and her children Tamara and Toby have no choice but also to live by her tyrannical rules. Q.E.D. follows Jean's voluntary entry into hospital and into a dramatic course of treatment. The question for her, her family and her doctors is can she ever be rescued from her obsession?