Henry Cavill on the craziest stunt he does in 'Mission: Impossible' – and the one Tom Cruise wouldn't let him attempt

Henry Cavill knew exactly what he was getting into when he signed up for Mission: Impossible – Fallout, the sixth installment in the Tom Cruise-starring series that’s become celebrated for the increasingly extreme lengths its creators will go to capture practical stunts.

“I saw it as an opportunity, and I wanted all in from the beginning,” Cavill told Yahoo Entertainment during a recent stop into our Los Angeles studios (watch above).

In one particularly intense sequence, Ethan Hunt (Cruise) and Cavill’s August Walker on engaged in a helicopter chase through the rigid mountains of Kashmir, India (actually filmed in a New Zealand valley). Cruise actually learned how to fly a chopper for the scene, while Cavill relied on his costar’s aerobatic acumen to capture the action.

“The room for error was so narrow,” said the 35-year-old actor best known for his role as Superman in DCEU films Man of Steel, Batman v Superman, and Justice League. “We’re flying through canyons [in] two helicopters that are maybe 6 feet from each other’s rotor blades. I could see the whites of Tom’s eyes…. I couldn’t hear anything either. I was completely deaf to direction… I was trying to work off what I needed to be doing off of his face. That’s how close we were.”

Because the helicopters were flying through such tight terrain, Cavill estimated their rotors were about four feet from the cliffs. “So if there’s just a little gust and someone just jigs too much one way, everyone’s dead.” (At one point crew members thought Cruise actually did die.)

Cavill wasn’t scared, though. “You’re not really terrified on the day. You’re just going through it. You’re trying to perform. I’m trying to mind read, because I can’t hear anything… You don’t really have time to think about how close to dying you really are. It’s more about, ‘The audience is going to love this.'”

There was one stunt that Cavill was not allowed to put his life on the line to authenticate the story: the now-famous HALO sequence in which cruise jumped out of an actual plane over 100 times to film.

“There’s other stunts where if I don’t have the right skillset for it, there’s a chance that people would die because I didn’t get it right,” he said, explaining why the skydive scene was his “giant heartbreak” but would have “resulted in death.”

Still, Cavill admits he’s not above pouting. “I was like a little kid. Really, really grumpy about it.

“I asked Tom, I said, ‘Let me do it, just put me in. I reckon I can do this.’ He said, ‘I know how you feel. I appreciate it. But you can’t do this… I’ve trained for hundreds of hours to do this jump. You’ve had wind tunnel training, and yeah, you’re good in the wind tunnel, that’s great. But you will probably end up killing all of us because there’s a point in the jump [where] the skillsets for both performers are needed to recover from the stunt. And if one doesn’t manage to do it, then it’s really bad. Bad things happen.”

Mission: Impossible – Fallout is now playing.

Watch Henry Cavill talk about his much-memed “arm reload” fight scene:

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