From a rejected script for the third Indiana Jones movie, written by Chris Columbus (yes, that's his real name). A few general ideas did make it into "The Last Crusade" (e.g. there's a boat chase, and a tank fight, and an artifact of longevity, and Indiana Jones is the protagonist), but there the resemblance ends. This is a bit too weird and fantastical to work as an Indiana Jones story (insert your own quip about "Kingdom of the Crystal Skull" also fitting that description here) but so help me, I still think it's pretty cool, so I replaced him with a different character and attempted to turn the script into a novel. Then I changed the different character back to Indy to give people a reason to give a crap. Just pretend the whole thing was a dream or something.