A woman with a suitcase is running from a man, and gets on a train to Chicago. The Baron just happens to be in the area and decides to help her. This gets him involved with gangster Tiger O'Leary, and a whole lot of trouble.
This book has a terrific start, is less in the middle, then limps to a stupid ending. Creasey gives in to 007mania in a plot that begins like a vintage crime thriller, then gets sillier and sillier as it progresses into an impossible MacGuffin and a improbable ending. Creasey does his best to sell it, but the task is beyond even his craftsmanship.