John Rhys Davies, Harrison Ford, Sean Connery and Denholm Elliott in a scene from the film 'Indiana Jones And The Last Crusade', 1989. (Photo by Paramount/Getty Images)

This year marks the 30th anniversary of Indiana Jones and The Last Crusade. For many fans, Last Crusade is the best of the series. It has a perfect blend of genuinely funny humour, compelling action, and imaginative challenges. The brilliance of all of these elements set it apart from the other two (superb) films in the original trilogy.

Of course, the less said about the fourth instalment, Indiana Jones and the Kingdom of the Crystal Skull, the better. But, believe it or not, Last Crusade was one draft away from potentially being as big of a disaster as Crystal Skull.

Read more: Indiana Jones 5 is still on track for a 2021 release

In a major lesson for screenwriters, narrative analyst Mike Fitzgerald has compared Last Crusade’s earlier drafts with the final draft, a draft that featured contributions from genius script doctor Tom Stoppard.

Director Steven Spielberg on the set of his film Indiana Jones and the Last Crusade. (Photo by Murray Close/Sygma/Sygma via Getty Images) More

Now, we in no way mean to denigrate the original author of the script, the fantastic Jeffrey Boam, whose credits include The Dead Zone, Innerspace, and The Lost Boys. It’s just Last Crusade wasn’t exactly his best work, until Stoppard’s changes were introduced.

You can read the entire report here, but we’ve pulled out some of Stoppard’s most significant changes, to show how the film was rescued from possible disaster.

The seagull sequence

Scottish actor Sean Connery as Professor Henry Jones in a scene from the film 'Indiana Jones and the Last Crusade', 1989. (Photo by Murray Close/Getty Images) More

This is a small change, but it has a memorable impact. In the original version of the script, Indy and Henry are faced with a plane that’s banking towards them. They have one bullet left, and things look bleak. Until Henry fires the bullet at a flock of seagulls, which fly into the plane and take it down.

Stoppard’s version has the pair completely out of bullets, with Henry forced to use his umbrella to stir up the seagulls. It’s one of the film’s best moments, and we can’t believe it was a last-minute addition. Just a beautiful bit of visual comedy.

The tank sequence

American actor Harrison Ford as the eponymous archaeologist in a scene from the film 'Indiana Jones and the Last Crusade', 1989. Here he hangs from the gun of a German tank during a chase scene. (Photo by Murray Close/Getty Images) More

The show-shopping set-piece of the final film was much shorter, and simpler in Boam’s original draft. Also, it originally ended with a gag that saw Indy’s pants falling down.

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