The movie features some classic action stars along with some familiar faces who know their way around a fight.
"It's a journey down to a genre they haven't seen for a while," Stallone said. "That's all I can account for. It's been gone so long that it's new again."
Stallone is the star, director and co-writer of the film. He gathered a cast of tough guys to tell the story of a group of mercenaries hired to overthrow the nasty dictator of a South American country, but they soon find themselves dealing with deceit and betrayal.
The actors couldn't say enough good things about the film and working together.
"It was just a great idea and we should have done it a long time ago, but I'm glad we did it now," Bruce Willis said.
"I think we all kind of had a mutual admiration and respect for each other and we got along great," added Randy Couture. "It was like a bunch of old brothers.
"Don't come in here looking for rocket science and, you know, a solution to the problems of the world," warned Steve Austin. "This is a good time."
"The nicest thing I do in this movie is I pull a girl's hair for 10 minutes," Eric Roberts said.
There is plenty of testosterone in this movie, but one of the stars insists the emotion is going to sneak up on you.
"You're going to go, 'Whoa, I can't believe Stallone did that to me,'" Terry Crews said. "You're going to feel like, whoa, I did not mean to get emotional, you know what I mean? This is a chick flick for guys."
"Tonight, I could go to bed and just be like, this is what it's like to be in a big budget movie," said actress Charisma Carpenter. "I mean, these fans are out of control on Hollywood Boulevard and it's just surreal."
It's Stallone flexing his action movie muscle.
"The Expendables" also features Jason Statham, Dolph Lundgren, Jet Li, Mickey Rourke and Gov. Arnold Schwarzenegger. It opens August 13.