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 (franchise) fact, rather than myth." MacGregor's favorite book was "The Seven Veils", which featured real-life explorer Percy Fawcett and the death of Indiana's wife, Deirdre Campbell. Martin Caidin wrote the next two novels in Bantam's series, "Indiana Jones and the Sky Pirates" and "Indiana Jones and the White Witch". These feature Gale Parker as Indiana's sidekick; they introduced afterwords to the series, regarding each novel's historical context. Caidin became ill, so Max McCoy took over in 1995 and wrote the final four novels: "Indiana Jones and the Philosopher's Stone", "Indiana Jones and the Dinosaur Eggs", "Indiana Jones and the Hollow Earth",