After working in asylums for nearly three decades, Valerie Martin is set to retire but one phone call changes everything and she finds herself on a train bound for Northampton and the asylum where her career began on the wards in 1959. Finding herself inside the walls for the first time in over a decade, Valerie begins one final clerical task for the Department of Mental Health, a job that forces her to relive her years at the asylum. As she digs through the files, uncovering memories long forgotten, Valerie discovers something else, a dark and dangerous secret that has remained buried in the basement records room for years. As she investigates further, Valerie must take a deeper look at her time at Northampton State Hospital, as well as the people who surrounded her, uncovering a mystery that threatens to change her forever.