Tom Cruise breathed in his own carbon dioxide while filming ‘Mission: Impossible 8’ scene

Tom Cruise pushed the limits while doing his own stunts for Mission: Impossible — The Final Reckoning.

In an interview with Empire magazine, Cruise said he breathed in his own carbon dioxide while filming a scene for the eighth Mission: Impossible movie.

During the sequence, Cruise’s character, Ethan Hunt, is underwater exploring the wreckage of a submarine. To film it, Cruise wore a specially designed suit and mask, but it is something he could only wear for 10 minutes at a time before suffering from hypoxia, or an absence of oxygen in body tissue.

“I’m breathing in my own carbon dioxide,” Cruise said. “It builds up in the body and affects the muscles. You have to overcome all of that while you’re doing it, and be present.”

The film’s director, Christopher McQuarrie, said shooting the sequence was “so challenging and so terrifying” and “really physically punishing” for Cruise.

“He’s in a rotating structure filled with debris, and you had to find a way to make that environment look as chaotic and unhinged as humanly possible,” McQuarrie said. “But in a way that you could repeat, and that Tom could navigate, and survive.”

Mission: Impossible — The Final Reckoning comes to theaters on May 23.