Kate Winslet reveals Titanic door scene was filmed in 'waist-height' tank: 'Leo is, I'm afraid, kneeling down'

Kate Winslet is pulling back the curtain on Titanic's movie magic.

In an interview with the Happy Sad Confused podcast, the Lee actress discussed filming the climactic sequence in which Rose floats on a door fragment as Leonardo DiCaprio's Jack freezes — and the conditions weren't nearly as perilous as they looked on screen. "That was quite an awkward tank, that one, because — to burst a bubble, it was waist-height, that tank," Winslet revealed. "Leo is, I'm afraid, kneeling down on the bottom of the tank."

Winslet said that the maneuverability of the tank allowed her to take frequent bathroom breaks without much trouble. "I was regularly like, 'Can I just go for a pee?'" she recalled. "And then I'd get up, get off the door, walk to the edge of the tank that was 20 feet away, and I'd literally have to fling my leg over and climb out of the tank and go for a pee, and then come back and crawl back on the door again. I know, it's terrible to admit these things."

The tank constantly recirculated water, which caused significant issues with the audio in the sequence. "The thing that was amazing about the edges of the tank was that it was an infinity tank, so there was constant water rushing, and you could hear the constant sound of water," Winslet said, noting that the cast had to re-record their lines after filming was completed. "Which, let me tell you, everybody, means that the last 22 minutes of that movie are entirely looped. Everything… completely looped the whole thing. I promise you, because you could hear this water noise the whole time."

The actress feared her words might cause her some trouble. "I shouldn't be saying any of these things," she said. "Jim Cameron's gonna be ringing me, like, 'Why are you telling them all that?'"

Winslet also recalled missing multiple opportunities to watch the film when it released in 1997. "When it premiered in London, I was really unwell," she said. "I had terrible food poisoning, and I was actually in hospital in London. It was completely weird. And then when it came out in the U.S., I actually was at the funeral of my boyfriend. I mean, it's a terrible thing to even think about now," she said about the death of her former partner Stephen Tredre. "So I sort of missed everything around the release of Titanic, which, I don't know, is that the universe's way of protecting me from something, or just reminding me to do the things that matter."

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The actress finally watched Titanic at a packed theater in New York. "I snuck in with two friends, and that was where I saw it for the first time," she said. "I just remember thinking, 'Oh my God. It's packed. That's weird. It's a packed theater. I'm in one of those films where actually people go and fill every seat.' That was quite strange."

Winslet's new drama Lee is now playing in theaters.

Watch the full conversation between Winslet and Josh Horowitz above.