Robert Pattinson Heard Matt Damon Screaming Through a Trailer Wall on Set and Figured He Was “A Complete Psycho.”

“He is such a nice guy… I thought he was on the phone and I thought he was a complete psycho. He was just screaming and screaming and screaming. I thought he was having a really bad toilet experience. He was just blowing his voice out just to sound older.”

Robert Pattinson, who plays Antinous, heard the whole thing from the trailer next door on the set of Christopher Nolan’s “The Odyssey” and told MTV UK he had no idea Matt Damon was blowing out his voice to sound older as Odysseus until someone explained it.

The vocal wrecking was one piece of a much larger transformation. Damon, 55, dropped to 167 lbs (his lightest since high school), cut gluten entirely on doctor’s advice, and described the prep as a “24-hour-a-day job” closer to training as a professional athlete than a normal movie shoot. Nolan refused prosthetics, so Damon grew a real beard for about a year. The days were so long the crew joked about the “Odyssey Five,” meaning 5 hours of sleep counted as a good night.

The rest of the cast went to similar lengths. John Leguizamo, playing the visually impaired swineherd Eumaeus, studied a friend with sight impairment and walked around his house in the dark. Tom Holland rehearsed fight scenes on a cliff edge and said his first day on set “scared the sh*t out of me.” The cast attended a rowing camp and physically rowed a roughly 100-ton ancient-style warship on days when the wind died, with Nolan shooting the sequences documentary-style instead of leaning on CGI.

Damon has called it “by far” the hardest movie he’s ever done.

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