You know how last week I said I was looking forward to how the Twelfth Doctor was going to act in an episode that didn't feature Clara Oswald at his side? Well it seems I might have jumped the gun a bit on that assessment, as Mummy on the Orient Express picks up some weeks after the events of last week's Kill the Moon. Written by another Doctor Who first time writer Jamie Mathieson, this episode places the duo on a rather silly but appropriate setting for a good old fashioned murder mystery adventure.