Vintage paperback copy of Bats Fly at Dusk, by A. A. Fair, pseudonym of Erle Stanley Gardner (Dell, 1947). Part of the Dell "mapback" series, with phenomenal art on both the front and back covers. Though described as a part of the "Cool and Lam" mystery series, in this book Lam is serving in the Navy and so is reduced to participating in the mystery via telegram, leaving Bertha Cool to solve the case. 

This book is in excellent condition for its age, with a tight spine and no rips, tears, or creases. A highly collectible book!