Progress on the potential fifth instalment of the Indiana Jones series is far from speeding ahead, so says its potential producer.
Frank Marshall, who has produced all the Indy films so far, along with the likes of 'The Goonies' and the 'Back To The Future' series, has even dampened hopes that it will happen at all.
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“I say, for me, [Kingdom of the Crystal Skull is] the last hurrah," he told Collider. "I know that yes, we talk about it, but there’s no idea, there’s no MacGuffin.”
The 'MacGuffin' he mentions is the plot device that is essential to drive a film along, a phrase initially used by Alfred Hitchcock and often used by Marshall's fellow Indy producer George Lucas.
Classic cinema MacGuffins have included the briefcase in 'Pulp Fiction', the falcon in 'The Maltese Falcon', and R2-D2 in 'Star Wars', the object that everyone wants to get hold of.
Steven Spielberg has been vocal about the critical failure of 'Indiana Jones and the Kingdom of the Crystal Skull', blaming a weak MacGuffin.
“I sympathize with people who didn't like the MacGuffin (the crystal skull) because I never liked the MacGuffin,” he said.
It has been previously reported that the fifth in the Jones series has a potential idea for a plot, but nothing more so far.