Beauty is pain, and all art means sacrifice, and no one knows this better than Gary Oldman, who gave himself nicotine poisoning to portray the most famous Prime Minister in British history.

Winston Churchill was a cigar fiend — “You can’t have Winston Churchill without a cigar,” director Joe Wright told The Hollywood Reporter for their fascinating behind-the-scenes look at how this winter’s awards contender Darkest Hour got made. They reportedly spent around $20,000 of the movie’s $30 million budget on Churchill’s beloved Romeo y Julieta Cubans for Oldman to smoke, and he says it almost made him seriously ill.

I got serious nicotine poisoning. You’d have a cigar that was three-quarters smoked and you’d light it up, and then over the course of a couple of takes, it would go down, and then the prop man would replenish me with a new cigar — we were doing that for 10 or 12 takes a scene.

The THR piece gives a great look at the trial and error process that goes into making one iconic-looking person look like a totally different one. Early attempts at prosthetics for Oldman were disastrous: “It was like Gary Oldman and Winston Churchill had a love child. And it wasn’t pretty,” Oldman said.

Finally they got it right, and ended up with a mattress-padding suit and silicone face mask, the entire outfit only weighing about 14 pounds, giving Oldman room for Churchill’s many gestures. The transformation was so complete that when a historian visited the set and saw test photos of Oldman hanging up on the wall, he thought they were real photos of the Prime Minister that he’d never seen before, and asked the crew where they’d gotten them.

The extras even gave Oldman a standing ovation the first time he delivered Churchill’s “blood, sweat, and tears” speech, a moment that Oldman himself describes as “a benchmark in my own career.” Darkest Hour opens December 22.

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