March 2020. Annie is alone in her house as the world shuts down, only the ghosts of her memories for company. But then she receives a phone call which plunges her deeper into the past.

1959. Annie and Rita are student nurses at Fairlie Hall mental hospital. Working long, gruelling hours, they soon learn that the only way to appease their terrifying matron is to follow the rules unthinkingly. But what is happening in the hospital's hidden side wards? And at what point does following the rules turn into complicity - and betrayal?

1983. Annie is reeling from the loss of her husband and struggling to face raising her daughter alone. Following a chance encounter, she offers a sick young man a bed for the night, a good deed that soon leads to another. Before long, she finds herself entering a new life of service - her home a haven for those who are cruelly shunned. But can we ever really atone?