Paul lives in the Welsh countryside with his wife Elise, and their two young children. Over in London, Cora plans to move back to Cardiff, to the house she has inherited from her parents. She is escaping her marriage, and the constrictions and disappointments of her life. Connecting them is the London train, and a chance meeting that will have immediate and far-reaching consequences for both Paul and for Cora.
It was meant to be a harmless stag night prank. A few hours later four of his best friends are dead and Michael Harrison has disappeared. With only three days to the wedding, Detective Superintendent Grace - a man haunted by the shadow of his own missing wife - is contacted by Michael's beautiful, distraught fiancée, Ashley Harper. Grace discovers that the one man who ought to know Michael Harrison's whereabouts...