All aboard a train bound for... murder. Kitty Underhay is looking forward to a week of long lunches and wedding planning with her husband-to-be, Captain Matthew Bryant. But the plan is derailed when he is called on to collect a former comrade-in-arms, arriving on the 15:50 from Bakerloo. As the train bearing Simon Travers pulls up to the platform, a piercing scream rises over the...