J. S. Fletcher - Rayner-Slade Amalgamation

Marshall Allerdyke is driving through the night from London to Hull in response to an urgent telegram from his cousin. As he nears Hull, a beautiful woman stops his car to ask for directions to Scotland. Odd time to be traveling so far and in such a hurry, but Allerdyke's mind is elsewhere. When he finally arrives in Hull, he finds his
cousin dead in his hotel room and a valuable consignment of jewels missing. Allerdyke's only clue rests with that woman hurrying off to Scotland.(Summary by MaryAnn)