The Big Sleep & Farewell, My Lovely (Modern Library)

These two classic novels featuring private eye Philip Marlowe made Raymond Chandler's name synonymous with America's hard-boiled school of crime fiction.  The Big Sleep was an instant success when first published in 1939.  It centers around a paralyzed California millionaire with two psychopathic daughters; he involves Marlowe in a case of blackmail that turns into murder.

Farewell My Lovely, which Chandler regarded as his finest work, came out the following year.  It has Marlowe dealing with the Los Angeles gambling circuit, a murder he stumbles upon, and three very beautiful but potentially deadly women.
"Chandler writes like a slumming angel and invests the sun-blinded streets of Los Angeles with a romantic presence," said Ross Macdonald.  And George V. Higgins wrote:  "Chandler is fun to read.  He's as bleak as tundra, and his dirtbag characters far outnumber his stellar citizens, but Philip Marlowe is a laconic tour guide through a zoo of truly interesting animals."