On a fast train to London, lawyer Arthur Crook meets trouble with a capital T. During the journey one passenger disappears and is subsequently found dead beside the line; and it is thanks to Crook's turn of speed that a second corpse isn't found there too. These events are part of a series of crimes planned by a man who has killed before and is preparing to kill again.

This is the gripping story of a girl in desperately dangerous circumstances flitting stealthily from one inconspicuous boarding-house to another and seeking safety in obscurity. Yet, ironically, it is Crook, the eccentric red-headed solicitor to whom obscurity is as unknown as it is undesired, who achieves her salvation after a life-and-death chase.