The 27-year-old actor was reportedly shooting in freezing temperatures near the Baltic Sea when he refused to let a stunt double perform the scene.
"It was in St Peter-Ording, on the north coast of Germany. They said I could use a double but I'd worked myself up to do it," the Daily Star quotes Smith as saying.
"So I went into the sea three times. It was the coldest I've ever been," he added. "The next shot we did, we were running along the beach and I was suddenly so frozen I just hit the deck. I couldn't move."
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