SANTA MONICA, California — "Well," grinned the legendary Sylvester Stallone on Tuesday night at a tiny screening room in Los Angeles, unspooling an extremely rough cut of "Rambo" for the first time. "Let the fun begin!"

With that, the lights went down and one-man-war-machine John Rambo walked onscreen for the first time in almost 20 years. The lucky few in attendance signed strict "no-review" legal forms, but this much we can tell you: It's the most violent "Rambo" yet, and is good enough to make "Rambo III" look like "Rocky V."

Before the screening, the charismatic Stallone introduced the film he wrote and directed, and in which he stars. "I wanted to be able to take Rambo and bring him up to modern-day sensibilities and deal with a more realistic view," he explained. "In this one here, I was dedicated to trying to do something more realistic."

With that in mind, he was willing to poke fun at his previous 1988 adventure, in which he battled Russians in Afghanistan. "The last 'Rambo,' it was [unrealistic]. You know, you don't walk around in a desert, in 130-degree heat, with a tank top on," Stallone laughed. "You'll get blistered on a beach in Miami in six hours! So, we definitely pushed that envelope a little too far."

When the film opens January 25, audiences will see Sly in a jungle environment, once again wielding his bow and arrow and extremely large knife. "I was looking for a subject that had both feet in reality, which is Burma," he said, referring to the country that is now officially called the "Union of Myanmar." "I called Soldier of Fortune magazine, and I said, 'What is the most underreported, egregious display of human-rights violations on the planet that no one knows about?' And they said Burma. [Abuses in the country have] been going on for 60 years, and it's a horror show, but it's a well-financed coup, and the propaganda machine buries all the atrocities that are going on there."

In Stallone's mind, it was the perfect backdrop for what he said is likely Rambo's final adventure. In the movie, the hero emerges from seclusion in Thailand to escort Christian missionaries on a humanitarian mission in Burma. The missionaries are later taken hostage.

"I thought this would be great, to be able to take the character and deal with a real-issue situation alongside some missionaries, and the mercenaries that go over there, and also provide some sort of entertainment," the burly star explained. "So, this is the end result of my foray into the Burmese situation — and maybe it's the last time I visit John Rambo."

Check out everything we've got on "Rambo."

Visit Movies on MTV.com for more from Hollywood, including news, reviews, interviews and more. For breaking news, celebrity columns, humor and more — updated around the clock — visit MTVMoviesBlog.com. Want trailers? Visit the Trailer Park for the newest, scariest and funniest coming attractions anywhere.