In a conversation with Vulture, Washington said he was waterboarded during the filming of his upcoming action-drama, "Safe House."
"I wanted to see what it would be like. It's strange. You can't breathe in, because the water comes in, and it's filling up your mouth," said Washington. "And that was just one time for a short time. Imagine having that done for 20, 30 seconds? You will give up the answers! You may not necessarily tell the truth, but you will tell [your captors] whatever they want to hear."
Although Washington was quick to volunteer, it didn't leave his director, Daniel Espinosa, feeling anymore at ease.
"I was terrified, but I let him go and I had to watch him do it. He went all out for this movie. I would definitely not like to be waterboarded. It was intense. Disturbing. I had sympathetic pain. I always get sympathetic pain. I wish I didn't. I felt like I was drowning."
Co-star Ryan Reynolds agreed, telling press recently that Washington's waterboarding was terrifying to watch.
"That was the most disturbing thing I think I'd ever seen, watching him be waterboarded," Reynolds said.
Waterboarding wasn't the only first Washington experienced on the set of "Safe House." During a fight scene with Reynolds, the Oscar-winning star received a black eye.
"I tried to make him feel bad about it," Washington said about the aftermath of one of Reynolds's errant punches. "I was like, 'What the!' I've never had a black eye in my life, but I can't say that anymore."
You can watch the infamous waterboarding scene -- as well as the part where Denzel gets a shiner -- when "Safe House" hits theaters this Friday.