Los Angeles, California - Kate Winslet went all out for the upcoming epic sci-fi sequel movie Avatar: The Way of Water, breaking an incredible stunt record held by action star Tom Cruise along the way.

The 47-year-old actor, who takes on the role of the underwater matriarch Ronal in the highly-anticipated film, had to shoot numerous scenes in a large swimming pool.

The new movie by director James Cameron actually takes place almost entirely underwater, allowing its viewers to see a whole new side of the planet Pandora.

Winslet had to undergo extensive training for her role and recently told The Hollywood Reporter how "completely phenomenal" it was for her, as a "person in her 40s who’s had three children," to master something new.

Celebrities Sean "Diddy" Combs bail ruling expected to come next week

She learned how to free dive and hold her breath underwater for long periods of time, and said she even shocked herself with the results of the "crazy, crazy, stuff."

"I knew quite quickly that it was definitely something [that] if I put my mind to it, I could probably get quite good, but I certainly never thought that I would hold my breath for seven minutes and 14 seconds," she said.

In fact, the 7:14 time has broken Tom Cruise's onscreen breath-holding record during Mission Impossible – Rogue Nation.

"I’m definitely better," Winslet joked.

Coincidentally, Cameron and Winslet previously worked together 25 years ago on an iconic movie scene also filmed in the water – AKA Titanic's "I'll never let go Jack" with Leonardo DiCaprio.

After her record-breaking time underwater, Winslet thought she may have died.

"I impressed myself. I thought I had died, because you come up from a breath hold and you're like, 'Have I died? Have I died?' You go into this weird headspace of, 'This could be what death feels like. Maybe I'm dead.' Because you close your eyes, you slow your heart rate down, you don't move. I'm staring at the bottom of a 25-feet-(deep) tank, so even your vision goes a bit weird. I was like, 'Yeah, I'm definitely dead.' And then finally when I realized, 'Oh, I am in fact about to die,'"she explained.

Director Cameron admitted he was "pissed" about Kate’s achievement when he heard.

Miley Cyrus Miley Cyrus gets sweet birthday tribute from Billy Ray Cyrus amid alleged rift

"I’ve been a free diver for 50 years and you smoked past me and everybody else," he joked.

The first Avatar film, released 13 years ago, became the highest-grossing film of all time – until it was surpassed by Avengers: Endgame in 2019 – and won three Oscars for its stunning visual effects, cinematography, and art direction.

The sequel, which is set in the year 2154, hits theaters on December 16.