In Mission Impossible: Final Reckoning, Tom Cruise makes more of an impression than usual. He’s well known for performing stunts himself, even the ones that professionals would advise against doing. And he goes above and beyond in the upcoming installment.
One particularly challenging stunt for Director Christopher McQuarrie involved setting up a large water tank designed to look like a submarine. In the scene, Cruise submerges himself in the 8.5-million-liter tank. McQuarrie faced the difficulty of capturing usable footage from a rotating structure, with debris flying around, while at the same time ensuring that Cruise was in the frame long enough for the correct shot.
Individually, these elements may seem manageable on their own. However, combining them into a single shot, frame, or sequence posed the challenge. Cruise's breathing apparatus, specifically, ran on a time limit.
With only ten minutes of breathable oxygen, all the moving pieces—no pun intended—had to work in harmony. From the chaotic debris floating in the prop submarine to Cruise focused directly in front of the camera, ensuring that the lens can capture his face in the diaphanous helmet, every element is crucial for the perfect shot. But for it to happen, Cruise stayed in the tank longer than recommended.
A human body can only remain submerged for so long before experiencing hypoxia. After about ten minutes, oxygen declines and becomes carbon dioxide. Not to be confused with monoxide, which is toxic, dioxide effects the muscles. Without the presence of oxygen, muscles break down, and can lead to catastrophic consequences if the hypoxia becomes severe or prolonged.
For context purposes, the scene in question centers around Cruise's character, Ethan Hunt, as he ventures down into the Sevastopol. The crashed remains house an artificial intelligence with the power to destroy the world—a typical conflict point in Mission Impossible movies. No right-minded individual would even bother diving into the wreckage for a psychotic AI, but with Gabriel (Esai Morales) intent on controlling it, Hunt has to beat his old foe to the punch. Ultimately, the franchise hero puts his life on the line for the world, yet again. More importantly, Ethan can't allow Gabriel—the man responsible for killing two of his loved ones—to become a megalomaniac ruler.
The bummer about this behind-the-scenes information is audiences now know that Ethan wins the race to Sevastopol. Dead Reckoning pointed to the pair fighting to reach the submarine first, but after seeing Ethan inside the floating submersible, it's clear that he beats Gabriel to it. Bear in mind that defeating the antagonist doesn't mean that he's neutralized the vicious AI. Accomplishing such a feat may require a bigger sacrifice.
Mission Impossible: Final Reckoning premieres in theaters on May 23, 2025.