During the night, a 30-year-old woman wakes up and tries to remember her life from her teenage years until the present day. But her dreams mix up with her memories.

London 1864. On a Hackney bound train, a guard discovers blood in a first class carriage - and a body on the railway embankment. For the first time, a murder has taken place on Britain's railways. Over a hundred years later, this single documentary for BBC Two uses the first hand testimony of the people involved at the…