4.50 From Paddington: Elspeth McGillicuddy is travelling on the 4.50 train from Paddington, London to St Mary Mead to visit her old friend, Miss Marple. On the way, the train draws to a halt and another train draws alongside it. In the carriage opposite, the window blind suddenly snaps up, revealing a tall, dark man strangling a woman to death. Almost immediately the train chugs away, leaving a shocked Mrs McGillicuddy to realise that she has witnessed a murder. At Bertram's Hotel: London, the mid 1950s. Miss Marple is staying at Bertram's Hotel in London. She loved the place as a girl and is delighted to find it remarkably unchanged. In fact, everything is too perfect. Beneath the well-polished Edwardian facade, Miss Jane Marple can sense something sinister? Nemesis: Set in the mid 1950s, Nemesis was Agatha Christie's last and one of her most complicated Miss Marple stories. A recently dead friend asks Miss Marple to investigate a crime.There are no clues - just a coach tour of historic homes and gardens. Murder is on the itinerary.