Indiana Jones Chronicles" explains how Indiana becomes solitary and less idealistic following his service in World War I. In "Indiana Jones and the Kingdom of the Crystal Skull", Jones is older and wiser, whereas his sidekicks Mutt and Mac are youthfully arrogant and greedy, respectively. Indiana Jones is modeled after the strong-jawed heroes of the matinée serials and pulp magazines that George Lucas and Steven Spielberg enjoyed in their childhoods (such as the Republic Pictures serials, and the Doc Savage series). Sir H. Rider Haggard's safari guide/big game hunter Allan Quatermain of "King Solomon's Mines", who dates back to 1885, is a
Indiana Jones and the Kingdom of the Crystal Skull of "Indiana Jones and the Last Crusade", Lucas let the series end as he felt he could not think of a good plot device to drive the next installment, and chose instead to produce "The Young Indiana Jones Chronicles" for TV, which explored the character in his early years. Harrison Ford played Indiana in one episode, narrating his adventures in 1920 Chicago. When Lucas shot Ford's role in December 1992, he realized the scene opened up the possibility of a film with an older Indiana set in the 1950s. The film could reflect a science fiction 1950s B-movie, with aliens