The story begins in 1921 with the birth of twins to the Demengels, a notable family who inhabit Celyn Lodge in Cornwall. Right from infancy, Lara becomes something of a thorn in the side of the Demengels, threatening to tear at the fabric of the family and bring shame upon their good name. From the age of eight, Lara is exiled to an annexe of the main house as her behaviour becomes increasingly oppositional and beyond the scope of her parents' control.

The only tangible relationship she has is with Nancy, the family's cook and long term employee. It is under the auspice of Nancy's care within the grounds of Celyn that Lara spends the next few years, growing increasingly feral and wholly estranged from the rest of her family. Her twin Milla is simultaneously living a genteel life and being groomed for an advantageous marriage like her older sister, Emmeline. Lara's very presence threatens the reputation and social standing the family enjoy.

In 1937, Lara's fortunes are set on a tragic trajectory in 24 hours that will forever change her life and have a ripple effect that will touch the lives of many. She is taken to Wellswood, an asylum for the mentally defective, a cruel and hostile environment where she will encounter gratuitous and conscious cruelty but will also find friendship and love she has not known before,

1975. Shelley Merrigan comes to Cornwall to start her nurse training. Nursing a broken heart, she leaves the warmth of her family and homeland in Wicklow, Ireland to start what she hopes will be a career where she can help and enhance lives. She begins her first placement on Cypress ward. Lara is the first patient she meets and she leaves an indelible impression. She is intrigued by the silent Lara Demengel, an enigma that piques her curiosity. As she digs deeper into her history she is unprepared for the collision course they are both on to an event that will bind them both forever. Shelley finds herself in an alien environment where callousness rather than care is the order of the day. Stymied by fear, she finds herself immobilised and unable to stand against the regime of tyranny on Cypress ward. Until she aligns herself with Doctor Vix Winstanley, she neither condones nor condemns the actions of senior staff.

The Quiet Room was ubiquitous in all of the old asylums. A sanctuary within a sanctuary; a place of low stimulation to escape the melee of the larger dayroom. They were underutilised except for study and meetings. It is in the pursuit of studying Lara's case notes that her story unfolds and the dehumanised Lara's history shapes all of their lives.