"I have to be honest. I think doing Titanic really taught me a lot about thinking ahead. When you read the script, Jack and Rose run through the flooded dining room. You have to know that's gonna be five days of shooting, because it was five days of shooting," Winslet told ET. "So it certainly helped me when I was reading this script. [You] just [have to] be very realistic about what was going to be required of us as actors."
Freezing temperatures were nothing new for Winslet, who was helicoptered alongside co-star Idris Elba and the film's crew to the peak of the Canadian Rockies each day while shooting The Mountains Between Us.
"I've never had so much luggage in my life with you know, the warm weather clothing.. the cold weather clothing and the boots and the scarves," she recalled. "I would have to allow 40 minutes every day just to make sure I had the layers right, the hotpacks on, and really be prepared."
"I would go up the mountain with my little backpack of my own survival stuff, and that usually included soup for me [and] soup for Idris," Winslet added.
While Winslet let co-star Leonardo DiCaprio take an ice bath at the end of Titanic -- for this movie, she insisted it be her who plunged into ice cold water for a scene where her character falls through thin ice.
"It was going to be dangerous. It was going to be extremely cold, so I did know," she said. "But at the same time, nothing can fully prepare you for how cold [it is]."