The actor was smoking "take after take after take" for his role in the new movie
Benedict Cumberbatch
Benedict Cumberbatch
| Credit: P. Lehman/Barcroft Media via Getty

Benedict Cumberbatch was committed to method acting for his role in the new movie The Power of the Dog, but it started to affect his health.

The 45-year-old actor plays Phil Burbank, a rough, chain-smoking rancher who abuses his new sister-in-law, played by Kirsten Dunst, and unexpectedly falls in love with her son. Cumberbatch committed to embodying Phil at all times on set, from playing the banjo to ignoring Dunst to learning to castrate a bull. He also picked up smoking, based on the book the movie is based on, where author Thomas Savage writes that Phil is always with a cigarette "perfectly rolled with one hand."

That lead to repeated health problems for Cumberbatch.

"That was really hard," he told Esquire. "Filterless rollies, just take after take after take. I gave myself nicotine poisoning three times. When you have to smoke a lot, it genuinely is horrible."

the power of the dog
Benedict Cumberbatch in The Power of the Dog

Nicotine poisoning occurs from excessive exposure to nicotine, and can cause nausea, vomiting, increased heart rate, headache, dizziness and fatigue, among other symptoms. In severe cases, it can cause seizures, respiratory failure, cardiac arrest or coma, and doctors often use activated charcoal to get it out of the body, according to the American Lung Association.

Along with picking up smoking, Cumberbatch also mostly gave up bathing to properly embody Phil.

"I wanted that layer of stink on me. I wanted people in the room to know what I smelt like," he said. "It was hard, though. It wasn't just in rehearsals. I was going out to eat and meet friends of Jane [Campion, the director] and stuff."

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Cumberbatch has dealt with some controversy for taking on the role. In the movie, set in 1967, Phil grapples with his sexuality after falling for Dunst's young son, and people have questioned why Cumberbatch, who is straight, earned the part.

"I feel very sensitive about representation, diversity, and inclusion," he said at the Telluride Film Festival in October about the role, according to IndieWire. "One of the appeals of the job was the idea that in this world, with this specific character, there was a lot that was private, hidden from view."

Cumberbatch added, "It wasn't done without thought."