Witness of Truth: The Railway Murders(2001)

Witness of Truth: The Railway Murders is a dramatised documentary examining the police investigation that brought David Mulcahy to justice for the brutal killings of three young women across the London area during the 1980s, alongside numerous sexual assaults. The case hinged on testimony from John Duffy, already imprisoned for life after his own conviction a decade earlier. At his original trial, Duffy had denied having an accomplice—a claim that would unravel years later when he revealed the truth to a psychologist behind bars. The investigation pieces together how this delayed confession finally exposed Mulcahy's involvement in one of Britain's most notorious crime sprees, reshaping a case that had haunted the capital for years.