DS Louisa Williams struggles against the odds to bring the serial killer to justice before he claims any more victims. Two women have already been brutally strangled and Louisa finds herself battling her new DI, as well as the odds, to catch the murderer. With her job on the line, she comes to rely on her colleague Millie and the handsome acting-DC Mark Ward in her fight for justice for the victims and for herself. Mark proves himself to be an invaluable member of the team and Louisa is quick to notice this and seeks his help throughout the case. Will Louisa be able to fit the pieces of this tangled investigation together before her DI transfers her back into uniform? What secret is DI Oakes hiding and will Louisa have the courage to reveal it?Look over your shoulder. You never know who's behind you.