What's the proper way for a Boston landlady to react when her most obnoxious boarder - curmudgeonly Barnwell Augustus Quiffen, gets squashed by a subway train? Sarah Kelling already has a far nicer applicant for the drawing room suite he lived in, but then an odd eye witness shows up on her doorstep, insisting somebody pushed Mr Quiffen under the train, and Sarah finds herself knee-deep in yet another mystery, aided by Max Bittersohn, an art expert with a very special sort of expertise...