Kevin Costner's morphine drip

Kevin Costner was on a morphine drip while filming 'Hidden Figures'.

The 69-year-old actor insisted he always tries to remain professional on set but revealed he was forced to go on morphine due to the pain he suffered from kidney stones during filming of the 2016 movie.

He told PEOPLE: "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'].

"I 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.

"I never missed a day of work but I sat in my trailer with a morphine drip in my arm.

"I wanted to cry, but there was everybody watching, so I didn't."

Meanwhile, 'Yellowstone' actor Kevin's latest passion project is epic Western 'Horizon: An American Saga'.

The opening movie in the saga marks Costner's first directorial outing for over 20 years but he knew he had to get behind the camera on a film that is so meaningful for him.

Kevin told The Hollywood Reporter: "Sometimes you wonder if you can still ride the bike, but what I knew was I believed so much in my story that I really was the one that needed to direct this.

"I didn't want to come away not bringing everything home that I thought the movie had a chance to deliver."