“I’ll be back.” The catchphrase that defined an era for sci-fi movie fans.

Arnold Schwarzenegger in and as "The Terminator" — the 1984 science fiction blockbuster that sealed his image as a box office juggernaut — is about as iconic as it gets, yet one of the film's most unforgettable sequences apparently happened by coincidence.

In a recent interview with the Hollywood Reporter released on Tuesday, Schwarzenegger described the catchphrase in the film, "I'll be back," as an "accident" caused by a disagreement with his director, James Cameron, reports CNN.

“Cameron and I were debating how to say the line because I was not comfortable with saying ‘I’ll,’” the former California governor reminisced. “I said, I think it’s stronger to say, ‘I will be back.’ Cameron said, ‘Are you the scriptwriter now? It’s just one word. Don’t tell me how to write. I don’t tell you how to act.’”

Schwarzenegger recalled his reaction, telling his director that he told him how to act "every f**king minute!"

But, in the end, the outspoken director triumphed, telling Schwarzenegger, “Arnold, you think it sounds weird. It doesn’t. What makes it great is that you sound different than me…That’s what makes it work.”

Cameron then told his star to “just say it 10 times. Say it different ways. I’ll keep rolling the camera. Then we’ll choose one.”

Of course, after a few trials, they found one that worked, said the report.

“The movie comes out. I’m in Central Park. This guy comes up and says, ‘Say the line!’” Schwarzenegger continued. The line has followed him to this day, he said, adding, “A few days ago, I was skiing in Aspen, and the concierge comes up asking me to say the line.”

“So that’s where it started and where it ended up. It’s wild.”

In other parts of the interview, Schwarzenegger stated that while he may be done playing the Terminator — a robot from the future entrusted with either saving or killing mankind, depending on whatever series edition you're talking about — the franchise itself "is not done."

“I’m done. I got the message loud and clear that the world wants to move on with a different theme when it comes to ‘The Terminator,’” he said. “Someone has to come up with a great idea. ‘The Terminator’ was largely responsible for my success, so I always would look at it very fondly. The first three movies were great.”