Sylvester Stallone has teased that the third Expendables film is "an event film", because of the huge cast.
The action man reprises his role as leader Barney Ross in the latest instalment, alongside returning co-stars Jason Statham, Jet Li, Dolph Lundgren and Arnold Schwarzenegger. They are joined by newcomers including Mel Gibson, Harrison Ford, Kelsey Grammer and Antonio Banderas.
"To get them all together is very, very rare. Life takes us all down very different paths, so to get them together is an event. We're trying to make an 'event movie', just like The Avengers," he told Collider.
"We've brought in even better actors. You get some real heart. This film has the most heart you're going to find in an action film, if you want to use that term. I look at it as more of an adventure rather than an action movie."
Sly praised the new cast members, saying: "Mel has been very gracious to be in our film. He's getting into some very physical shape for this. He's not taking it lightly at all; I'm getting worried!
"And Harrison brought a certain kind of elegance and class. Kelsey's a great comedian, great actor. So you're going to see him do something new. It's a very interesting role."
Clint Eastwood and Jack Nicholson are on the 67-year-old's wishlist to appear.
"Clint is so involved with what he's doing, so that's a pipe dream. We got there a little too late because Jack Nicholson had said he might be interested in it, so there are still interesting avenues out there," he said.
"I want to get, if possible, the most unique actors from the past and just put them on there once and for all, if we can."
The Expendables 3 will be released in August.