The Little Sister is a 1949 novel by Raymond Chandler, the fifth in his popular Philip Marlowe series.
The story opens when mousy Orfamay Quest first phones and then visits Philip Marlowe's office in search of a detective. Orfamay is a "small, neat, rather prissy-looking girl with primly smooth brown hair and rimless glasses" from Manhattan, Kansas who has come to Los Angeles to search for her older brother Orrin. Orrin had recently come out to nearby Bay City (a fictional tough town that appears in many Chandler novels, modeled on the aircraft manufacturing sections of Santa Monica) to work as an engineer for the Cal-Western Aircraft Company, but has in recent months stopped writing to Orfamay and their mother. Orfamay describes her concern to Marlowe and asks that he find the whereabouts of her brother, despite giving Marlowe few leads with which to work.
During his search for Orrin, Marlowe runs into movie starlets, gangsters, suspicious cops and, most disturbingly, corpses with ice-picks jammed in their necks.