Jason Reitman’s work on the upcoming “Ghostbusters” sequel has led him to an amazing discovery.

The director appeared at Ghostbusters Fan Fest over the weekend alongside his father, the original film’s director Ivan Reitman.

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On-stage, the pair shared a collection of never-before-sceen footage from the original 1984 “Ghostbusters”.

“In making this movie, we found something kind of extraordinary,” Jason said. “We went to Sony, and we said, ‘We’d really love to get back into the original dailies from 1984. Do you still have them?’ And we found them.”

He added, “They were in a mine in Kansas, and we shipped the boxes to Burbank. And we’ve been going through the footage for reasons I cannot tell you, but along the way we found some really cool stuff.”

At the event, Jason also teased that he is likely to start shooting the new sequel in just over a month.

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He also revealed to fans that the original film’s cast have all read the script, including Sigourney Weaver, Bill Murray, Dan Aykroyd and Ernie Hudson.

The new “Ghostbusters” is set for release July 10, 2020.