 The character Lew Harper is based on novelist  Ross Macdonald (I) (qv)s character Lew Archer. The name was  changed for the film supposedly because Paul Newman (I) (qv) had  recently enjoyed success with _Hud (1963)_ (qv) and the producers  wanted the movies title to begin with "H". Also, the Macdonald  estate did not want the name "Archer" used in the movie.