Thirty years ago Monday, "First Blood" hit movie screens, introducing audiences to John Rambo, the embattled Vietnam veteran played on screen by Sylvester Stallone. The movie was an enormous hit, earning $125 million worldwide on just a $14 million budget. The violent, R-rated action thriller spawned three sequels, video games, and, improbably, an animated series for kids. And it established Stallone as a major Hollywood star outside of his "Rocky" series. But none of that might have happened if they had stuck with the original ending for the movie where Rambo didn't survive.

In the theatrical version, Rambo is cornered in a police station. He has his gun aimed at Teasle (Brian Dennehy), the sheriff who pushed Rambo to lash out in violence. But then his old commanding officer Trautman (Richard Crenna) orders him to stop. Rambo breaks down, telling Trautman how Vietnam scarred him and that he can't find a place in the civilian world. Then he gives himself up, and the film ends with him being taken away by the police.

That ending was changed after test audiences rejected the much darker original ending. The first scripted and filmed ending saw the trapped Rambo pleading with Trautman to kill him. Rambo says, "I can't spend the rest of my life in a cell. If I've got to die, I want you to do it." Trautman flinches, but Rambo insists: "You trained me. You made me. You kill me. You owe me that." Rambo places a pistol in Trautman's hand. He tries to aim away, but Rambo pulls the gun towards him and it goes off. It ends with Trautman walking away as Rambo dies alone. You can see the original ending in the deleted scenes in the "Rambo - The Complete Collection" DVD and Blu-ray set.

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The ending where Rambo survived was actually Stallone's idea. He had co-written the screenplay, and in the middle of shooting felt that audiences might feel too sympathetic to Rambo to want to see him die. He insisted that they film both versions during production, and when the audience at a test screening objected to the death scene, the other ending was switched in.

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Just getting "First Blood" to the screen was a challenge unto itself. It took more than a decade to adapt David Morrell's 1972 novel into a movie. Many huge stars were considered for the lead role of John Rambo, including Al Pacino, Dustin Hoffman, Robert De Niro, and Clint Eastwood. Kirk Douglas was originally cast as Trautman, and he told Movieline that is was his idea for the character to kill Rambo at the end. But he dropped out and was replaced by Crenna at the last moment.

"First Blood" gave Stallone his second blockbuster hit of 1982, coming only five months after the enormous success of "Rocky III." But it helped establish him as a true action star, not just a guy in boxing trunks. Stallone followed "First Blood" with two even more successful sequels in the '80s, then returned to the character after a 20 year break with 2008's "Rambo."

Stallone had originally stated that he might be up for a fifth film, but in 2010 he told Empire Magazine, "I think Rambo's pretty well done. I don't think there'll be any more. I'm about 99 per cent sure." That doesn't mean he's packed up his guns, though. His last film, "The Expendables 2," made $290 million worldwide this past summer, and there's already talk about a third.

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And who knows? They couldn't kill Rambo thirty years ago, so you should never count him out.

Watch Sylvester Stallone in the trailer for 'Rambo':

'Rambo' Theatrical Trailer