Christopher Lloyd Was 'Worried' About Michael J. Fox Replacing Eric Stoltz in 'Back to the Future'

Lloyd recalled having “no idea there was a change coming” in terms of the production’s decision to bring in Fox, 60, as a replacement for Stoltz, also now 60.

“We were shooting the mall beginning sequence, and we were asked to come to one of the trailers at one o’clock in the morning,” he said. “[Steven] Spielbergwas there, and he made the announcement of the change.”

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According to Lloyd, they had already been shooting for six weeks — and his “biggest fear was that, because I was really working to get Doc right … I thought, ‘I don’t know if I can get it up to do [all my scenes over] again.’ "

“So I was worried about it. But it all worked out,” said theEmmywinner.

He also called Stoltz “a wonderful actor,” but said the powers that be “decided that they needed somebody with a comic flair.”

“Michael,we had a chemistry which lastedthe whole time,” Lloyd said. “We could come back after a break and just be there [in the scene]. We didn’t have to work for it.”

Other actors who werein the running for the part of Marty, which was Fox’s breakout film role, includedBen Stiller,C. Thomas Howell,Billy Zane,Jon Cryer,Johnny Depp,Charlie Sheen,John CusackandRalph Macchio.

Lloyd also posted a snapfrom their reunion, which showed the duo in the middle of a conversation while sitting on a set of tall stools.

“Caption this … " he wrotealongside the candid shot.

source: people.com