Thomas Pitt is the powerful head of Britain's Special Branch, and some people fear that he may have been promoted beyond his abilities. He, too, has moments of self-doubt, especially as rumors reach him of a plot to blow up connections on the Dover-London rail line, on which Austrian duke Alois Habsburg is soon to travel to visit his royal English kin. Why would anyone destroy an entire train to kill one person-- or are the rumors designed to distract Pitt from an even more devastating plot?