Continuing the adventures of Penrod Schofield begun by Tarkington in 1914, this book is a crowning achievment of American boyhood for the ages, centering around a fantasy by Penrod and his pals that they are super sleuths and private eyes extraordinaire. A background in the previous two novels will help; this is the least stand alone work in the trilogy; and an understanding of temporal context and attitudes is a must, but this inexplicably obscure work of th American canon is a pure and simple joy as well as an indispensable volume of turn of the 20th century Americana and a keystone of the genre alongside Frank Merriwell and Tom Sawyer.