Kate Winslet: The Scene in Mountain Between Us with Idris Elba that Still Gives Her Nightmares

Yes, it's just acting. But when you add the snow, the ice, the high elevation, the cold and a tank full of water, things get very real, very fast.

So found Kate Winslet and Idris Elba while shooting the survival drama "The Mountain Between Us," about two strangers who must work together to save themselves after their plane crashes in a frigid wilderness.

"When we went up onto the mountain, we were one of the crew. If you needed a place to sit down you had to ... just find a patch of snow," Winslet tells Made in Hollywood reporter Kylie Erica Mar. "We did everything. It was 10,000 feet. It was freezing-cold temperatures. It was very deep snow. And I would ask a lot of questions: Where's the safety guys? I don't like the look of that slope. That looks a bit avalanche-y. What can you tell me about the chances about that one going over there?"

https://www.youtube.com/watch?v=B4GodWqO5iA

Elba says that while the location shooting in remote British Columbia was "well thought-out, well planned," the experience "was like an expedition every day, all of us. We all got powered up and warmed and shot this thing."

It also meant a return to the water tank for Winslet, who shot the climactic scene of "Titanic" bobbing on the water. She still shudders when thinking about a "Mountain Between Us Scene" in which Elba has to rescue her from a plunge into icy waters.

"It doesn't look it, it was very hard for Idris," she says. "I couldn't help because I was doing dead-person acting. I couldn't even like push with my foot or do any kind of shimmying or anything. I just had to be that dead weight. And I found that really, really hard, because I could hear him going ewwwaaahhh."

"Kate is my mate," says Elba. "I just felt a real sense of responsibility pulling her out."

Winslet says, "I did have dreams about being trapped under ice afterwards."