Donnington Manor: Enigma Express: The Lady Vanishes

It's 1941 and the Enigma Express is travelling from Dover to London. In what would seem to be an otherwise ordinary train journey, you notice that an inconspicuous old lady travelling alone has mysteriously disappeared between stops. To make the situation more curious, she has left her handbag behind in the carriage, beside it a strange encrypted note. Sensing there is more here than meets the eye coupled with a need of urgency, you decide to search her handbag and the carriage for clues to help you decrypt the message and perhaps discover the truth behind her disappearance. You need to be quick. Can you get to the truth before the train gets to its destination?