Judy Greer Admits She Was 'Starstruck' by Mark Hamill on the Set of “The Long Walk” (Exclusive)

Judy Greer knows Hollywood royalty erstwhile she sees it.

Speaking pinch PEOPLE astir her caller movie The Long Walk, nan character opened up astir moving pinch nan talented formed that included lead Cooper Hoffman and Star Wars fable Mark Hamill.

Asked what she and her castmates did to unwind while not filming nan harrowing scenes that nan thriller is chock afloat of, Greer, 50, admits, "I was ever a small starstruck by Mark Hamill, truthful whenever he was astir me, I had a difficult clip unwinding."

On nan flip side, she and Cooper — who had his breakout domiciled successful 2021's Licorice Pizza — felt for illustration they'd ever known each different erstwhile they met for nan film, successful which they play mother and son.

"Cooper and I, connected infinitesimal one, instantly had awesome chemistry and loved each different and started laughing correct away," Greer says. "Even though nan scenes were not funny, we were conscionable having truthful overmuch nosy connected set, truthful that was really easy."

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"I consciousness for illustration I've known him my full life," she continues of Cooper, 22. "And technically, I astir apt could person known him his full life — I didn't, but I consciousness for illustration I have. So that made it simple."

Cooper — boy of nan precocious Philip Seymour Hoffman — plays Ray Garraty, a teen successful a grueling title to beryllium nan past 1 opinionated successful a group of boys looking to either deed it rich | aliases dice trying astatine nan hands of nan villainous Major (Hamill, 73), who enforces nan totalitarian regime’s sadistic rituals.

Greer plays Ginny Garraty, a characteristic who has already seen calamity successful her family but who still supports her boy moreover arsenic she tin almost consciousness him slipping done her fingers successful existent time.

For a movie of this type, Greer tells PEOPLE, "They're truthful difficult emotionally that you person thing but to merchandise nan unit valve, truthful they do thin to strangely beryllium nan much nosy movies to shoot."

"It's interesting, because while evidently Stephen King is nan begetter of scary ... this movie is horror, but it's psychological to me, and truthful sometimes that is moreover harder emotionally," she explains.

Directed by Francis Lawrence and adapted from King’s 1979 dystopian caller of nan aforesaid name, The Long Walk costars David Jonsson, Ben Wang, Charlie Plummer, Garrett Wareing, Tut Nyuot and different young stars participating successful nan deadly stepping title alongside Cooper's Ray.

Recalling nan biggest challenges of shooting, which saw nan young actors walking astir 400 miles, Greer says, "It was really basking — it was summertime successful Winnipeg. Those mediocre kids ... they were stepping truthful overmuch each day, each day. Someone was ever handing retired h2o and Gatorade."

"I wasn't location for each of it, obviously, but my hats disconnected to those actors, because they really did it," she adds. "They really had to beryllium extracurricular stepping each nan time; that's not faked."

The Long Walk is successful theaters now.