Charlize Theron and Michael Fassbender Star In Steamy W magazine photo shoot

More important than the question of chicken-or-egg in the film industry is the burning movie debate: Death or sex?

In an interview for the August cover of W magazine, “Prometheus” costars Charlize Theron and Michael Fassbender ponder which of the two movie staples are harder to film.

Fassbender, 35, who came to fame recently with his 2011 sex-addiction hit “Shame,” noted that for him, being intimate onscreen is more difficult.

“I don’t know. Sex scenes sound like more fun than they are,” he told the magazine. “Death scenes are easier, really. Maybe because I’ve died so many times. I’ve had a lot of practice. In my movies, I’m often naked or dying.”

In fact, in “Inglorious Basterds,” Fassbender got his “testicles blown off through my a–. …It was a great death.”

And before then, in 2008′s “Hunger,” the actor had to slowly starve to death on the big screen. The role was actually the first that Theron, 36, ever saw him in.

“A friend said, ‘You have to see this movie. It’s the best thing I’ve seen in my entire life,’” Theron recalled. “I thought, Just chill out, okay? But I was absolutely blown away by it. It was, like, all bets are off from now on. This is the guy.”

For the “Monster” star, the debate between death and sex comes down to who she’s sharing the screen with.

“It depends on who you’re doing the sex scene with,” she said. “I don’t have issues getting naked (pauses). That sounds very slutty.

“What I mean is, I’m not hung up on my body, and I’ve been lucky to work with people I’ve been really comfortable with.

“And Michael’s one of the two who did not make me feel very comfortable,” she joked.

“I was a robot!” Fassbender exclaimed.