Samantha Laschen, a doctor specializing in post-traumatic stress disorder, has moved to the Essex Coast with her small daughter, Elsie, to escape the problems of her London life, or so she thinks. Fiona McKenzie barely survived the savage, murderous attack which left her parents dead. Now she is in need of sanctuary and the police see Sam as the ideal person to offer her a safe house. Already overburdened with the demands of a new job and her mercurial lover Danny, Sam reluctantly agrees to take her in. But as Fiona makes her way into the hearts of her hosts, Sam discovers that the risks she has foreseen are nothing compared to the terrifying danger she actually faces.