Killed Without a Trace explores the huge task facing police forces and prosecutors across the UK as they try to get justice for families and prove a murder has happened without that vital piece of evidence – the body.British actress Joanna Scanlan explores these remarkable and unconventional investigations, uncovering the lengths detectives must go to prove a murder has occurred. Joanna also reveals the heart-rending stories of families who, despite seeing a killer brought to justice, never had the chance to lay their loved ones to rest and are still searching for closure all these years later.This Crime + Investigation commission includes interviews from detectives leading the investigations, prosecutors, experts who helped to establish ‘no proof of life' and firsthand testimonies from friends and family.