Inside Britain’s MOST COMPLEX Serial Killer Investigation | The Railway Murders

In the mid-1980s, British serial killers John Francis Duffy and David Mulcahy carried their shared obsessions into adulthood, forming a violent partnership linked to the Railway Murders. Part 3 of Untold: The Railway Murders explores one of Britain’s most complex serial killer cases, examining how two friends committed crimes across the UK railway network. Through police interviews, offender profiling, interrogations, and forensic breakthroughs, this episode traces how one suspect was identified — and how DNA evidence later exposed the other. With years of confusion, missed links, and investigative breakthroughs, this case became a landmark moment in British criminal investigation. A disturbing true crime documentary showing how collaboration escalated abuse into murder — and how police finally closed in. 🔔SUBSCRIBE HERE -    / @_theclinic   Untold: Railway Murders Playlist -    • Untold: Railway Murders