Hunter S. Thompson ( July 18 , 1937 â `` February 20 , 2005 ) was an American writer . Hunter Stockton Thompson ( July 18 , 1937 â `` February 20 , 2005 ) was an American journalist and actor who wrote Fear and Loathing in Las Vegas ( 1971 ) and Fear and Loathing on the Campaign Trail '72 ( 1973 ) .