When the 20-year old daughter of Vaudeville star Lily Langtreet turns up dead at the foot of Mount Monadnock in the summer of 1910, the local police call it an accident. But residents of the Halfway House hotel, where she was staying, are certain she was murdered and call on retired Boston Police detective Robert de la Tour to help solve the mystery. Robert's journalist brother, Eugene, helps interview the guests, including, Mark Twain, Robert Frost, Red Sox pitcher Smoky Joe Wood, prizefighter Jack Johnson, mystery writer Mary Rinehart and a young Franklin Roosevelt.