Die-hard fans of Indiana Jones claim to know everything about the series -- even the stuff that happened off-camera. Trivia buffs probably know that Tom Selleck almost took the part before a 'Magnum P.I.' scheduling conflict got in the way; that the 10-second fight scene with the swordsman was motivated by Harrison Ford's real-life bout with dysentery; that 'Temple of Doom' is one of the main reasons Hollywood came up with the PG-13 rating; and that Sean Connery was cast in 'Last Crusade' as inside joke on the idea that James Bond was Indiana Jones' father. However! Here's a new piece of trivia that you may not know: remember the creepy, face-melting contents of the Ark of the Covenant in 'Raiders of the Lost Ark'? Steven Spielberg didn't actually know what they were going to be when he shot the movie.