The final film was written by Jeffrey Boam , but several famous "drafts" by other writers helped shape the story:
The final draft included some of the franchise's most memorable lines: "Don't call me Junior!"
Though uncredited, playwright Tom Stoppard did a final "draft" to refine the dialogue, particularly the witty exchanges and the emotional beats during the Grail trials. Iconic Quotes from the Script Indiana Jones y La Ultima Cruzada
This version introduced the Holy Grail as the central artifact and established the father-son dynamic. However, it was considered too serious and lacked the humor of the finished movie.
"I should have mailed it to the Marx Brothers." The Grail Knight: "He chose... poorly." The final film was written by Jeffrey Boam
And who's gonna come to save you, JUNIOR? Indiana Jones: DON'T call me Junior! Quotes - Indiana Jones and the Last Crusade (1989) - IMDb
And who's gonna come to save you, JUNIOR? Indiana Jones: DON'T call me Junior! "I should have mailed it to the Marx Brothers
Titled Indiana Jones and the Monkey King , this draft featured Indy battling a ghost in Scotland and eventually searching for a "fountain of youth" in Africa. It included a sequence with a tank chase, which was one of the few elements kept for the final film.