Anna Katharine Green was the most famous and prolific writer of detective fiction in the United States prior to Dashiell Hammett. Her first novel, The Leavenworth Case, was the bestseller of 1878. Green is credited with a number of “firsts” within the mystery genre, including the gentleman murdered as he makes out his will and the icicle as murder weapon. She created the first female detectives in American fiction. Her amateur spinster sleuth, Amelia Butterworth, became the prototype for numerous women detectives to follow, including Agatha Christie’s Miss Marple. Nosy, opinionated, and tenacious, Amelia Butterworth engages in a sustained rivalry with Ebenezer Gryce, a police detective. In the interaction between these characters, Green developed two more conventions adopted by future generations of mystery writers: the investigation as battle between the sexes and between the professional and the unexpectedly sharp, observant amateur. This volume presents two of Green’s Amelia Butterworth tales: That Affair Next Door (1897) and Lost Man’s Lane (1898).