The young woman had been in the loft for quite a while... dead. Discovered by two new tenants Michael and his heavily pregnant partner Vidya, it turns out that the heavily decomposed body belongs to a previous resident, Melissa, who hasn't been seen in more than two years and hasn't even been reported missing. DI Len Harper, in the process of retiring but not yet ready to let go, decides to follow up on a case that is already half-buried by his police colleagues. As he looks deeper into Melissa's story, he begins to open doors in the shared flats that have long remained closed hiding secrets any of which could lead to a killer. Partners in business and love, Elaine and Peggy, shared a turbulent relationship with the young girl. The divorced news editor Kieron and his damaged son Adam, what do they know and how much will they reveal? And the aging teacher who has lived in the house for fifteen years; apparently he lives alone, but appearances can be deceptive. Who we are behind closed doors is at the heart of a riveting murder mystery that grips until the darkest truths are revealed.