Kate Winslet reveals surprising facts about Leonardo DiCaprio's death scene in Titanic.

Leonardo DiCaprio got down on one knee for Kate Winslet in a crucial “Titanic” scene.

Winslet, 48, spoke about the Oscar-winning 1997 film at a screening of her new film “Lee” at the 92nd Street Y in New York City on Monday, September 23. Spilled during a question-and-answer session Winslet some tea about the film's notoriety and much-discussed door scene, according to People.

Winslet suspected that co-star DiCaprio had “post-traumatic stress disorder” because he was constantly asked about the scene in which – spoiler alert – he freezes to death because of a floating door that Winslet's character Rose has Space for him is sought after the sinking of the Titanic.

“Well, that was a pretty strange tank,” Winslet said of the giant water tank used to film the scene. “To burst the bubble, it was waist high back then.”

“I’m sorry to say that Leo knelt down. “I shouldn't say it – Jimmy Cameron will call me anyway,” the actress joked, referring to the film's director, James Cameron.

Although the tank's blueprints turned out to be less than ideal for DiCaprio, Winslet had one major advantage: she could easily go to the toilet.

“First of all, I regularly asked myself, 'Can I just go to the bathroom?' And then I get up, walk away from the door, go to the edge of the tank, about 20 feet away, and I literally have to throw my leg over and climb up and get back to the door,” she recalls. “It's terrible.”

She added: “The amazing thing about the edges of the tank was actually that it was an infinity tank. So there was constant rushing water and you could hear the constant sound of the water.”

This sound, according to Winslet, meant that all the actors were “completely on a loop” for the “last 22 minutes” of the film, “because you can hear that water sound the whole time.”

Looping or ADR is a process performed after a film has completed filming that, among other things, allows actors to re-record dialogue that was not audible or usable when recorded on set.

The Oscar winner also revealed that she secretly snuck into screenings of Titanic when it was released after missing the film's premieres in London and Los Angeles.

“When it premiered in London I felt really bad. I had terrible food poisoning and was actually in hospital in London, really strange. And then when it came out in the US, I was actually at a friend's funeral,” the Mare of Easttown star shared.

“I mean, it's horrible to even think about it now. And of course I didn't want to miss that, so I somehow missed everything about the release of Titanic that I don't know. Is this the universe’s way of protecting me, or is it just reminding me to do the things that matter?”

When she actually saw the film in front of an audience in a “crowded theater” and slipped into the screenings unnoticed, she found it “pretty strange.”

The actress has spoken fondly of “Titanic” throughout her career and hasn't shied away from discussing the blockbuster that made her a superstar.

And although she struggled with overnight fame after the film made a splash, she feels differently today. “It’s not a burden at all,” Winslet told Porter in February.

“(Titanic) continues to bring great joy to people. The only time I say, 'Oh God, hide,' is when we're on a boat somewhere.”

Winslet's latest film, “Lee,” hits U.S. theaters on September 27th.