Kevin Costner got candid about a health battle he dealt with while filming the 2016 biographical drama film.

The "Hidden Figures" artist revealed in an exclusive interview with People released Saturday that he was very sick while filming Theodore Melfi and Allison Schroeder's film. He said he developed kidney stones while filming and had to be on morphine for pain management.

"I've never worked drunk on a set. I've never worked high on a set, but I was on morphine the last two weeks that I worked on ['Hidden Figures']," he revealed.

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Kevin Costner
Kevin Costner attends the "Horizon: An American Saga" Red Carpet at the 77th annual Cannes Film Festival at Palais des Festivals on May 19, 2024 in Cannes, France.
(Photo : Gareth Cattermole/Getty Images)

He added that he "worked 10 days under an IV drip. I don't even know how. About three days of it I was normal, and then something happened to me."

Because of the bruises left by the IV needles on his arms, he reportedly had to keep his sleeves rolled down to hide them.

"I wanted to cry, but there was everybody watching (sic), so I didn't," he recalled.

Despite this health battle, he pulled off the role of Al Harrison in the film and "never missed a day of work" and just "sat in my trailer with a morphine drip in my arm."

 

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Talking about how he instilled a remarkable work ethic, Costner said in another interview that he learned it from his father.

"My father would never let another man outwork him," he said, adding that his imagination always "ran and ran and ran."

The 69-year-old actor also earned praise from his 15-year-old son Hayes, who worked with him on the set of his upcoming summer film, "Horizon: An American Saga."

 

Hayes, who made his acting debut in his dad's film as Nathaniel Kittredge, told ET Online during the movie premiere how it was working with the veteran actor.

"I got to spend the whole day with him every day and just see him work... I had such a blast. I just thought it was really cool, and it was an amazing experience," he said.

"I was just really proud of my dad. He's been working so long. I could just only think about my dad in that moment."