The last words Nick Walton hears from his fianc?e, Logan Somervile, are in a terrified mobile phone call from her. She has just driven into the underground car park beneath the block of flats where they live in Brighton. Then she screams and the phone goes dead. The police are on the scene within minutes, but Logan has vanished, leaving behind her neatly parked car and telephone.That same afternoon, workmen digging up an old asphalt pat in a park...