Veteran star Sylvester Stallone and his biceps are back on the big screen for the fourth Rambo film, which sees the 61-year-old don khakis to play the action hero one last time.
By Helen Bushby
BBC News entertainment reporter
He may be a good deal older and craggier than when he first starred as Vietnam veteran John Rambo, but this did not deter Stallone from plunging himself deep into the treacherous jungles of south-east Asia, where the film is set.
The movie, which was released in the US in January, has had mixed reviews, with Variety singling out its "unusually high body count" for criticism.
In the film, Rambo has become a pacifist recluse in Thailand who reluctantly helps guide a group of Christian missionaries to Burma by river.
When he hears of their capture by the Burmese army in the thick of a civil war, he steps in to help.
According to the film's publicity, "what follows is a descent into hell on earth".
Stallone is unrepentant about the film being described as "horrific and bloody", saying: "That's what war is. It's not gratuitous violence.
"Gratuitous violence is a guy dressed up in a fright wig with a meat cleaver chasing 10 teenagers around the woods for 10 hours.
TWO DECADES OF RAMBO
Rambo - 2008
Rambo III - 1988
Rambo: First Blood Part II - 1985
Rambo: First Blood - 1982
"This is civil war, which is by far the most vicious of all wars."
But the star, who also directed and wrote the film, said its exploits did not compare with what the people of Burma have to endure.
They are in the midst of a 60-year conflict between the ruling military and the Karen tribespeople, who want independence.
Stallone claims to have done "tons and tons" of research for the film. He worked with the Free Burma Rangers, uncovering what he calls "an unbelievable amount of material on the atrocities".
Denied permission to film in Burma, the movie was made in neighbouring Thailand - but the shoot was still dogged with trouble.
"We were getting an abundant amount of death threats," he explains.
"The Burmese police in cities up and down the Salween River made their presence known. So the king [of Thailand] was nice enough to give us his border patrol. It was a pretty tense situation."
The crew also suffered physical hardships - many of them were "on saline drips during filming", he says, adding "everyone was getting bitten, everyone was getting sewn up".
Filming in the jungle proved treacherous
"I kept going 'is anything around here nice?' Even the butterflies are deadly!"
Stallone himself ended up in hospital with a blue arm from a "giant haematoma" after landing on a cactus during one of his own stunts.
"Even walking into your motorhome, you find something in your toilet that will eat you. It's dangerous - how do these people live, man?" he asks.
He decided to revive Rambo because "I thought that might be an interesting revisit for an entire generation. It's savage, and whoever's the bigger savage wins."
The actor, who lost 20kg for the role, is hoping to reap the success of the earlier Rambo films and, presumably, to avoid any more Razzie awards, having won eight over the years.
But Stallone is no lightweight when it comes to box office and critical success.
He scored a commercial hit by revisiting his other iconic character, Rocky, for a sixth and final time in 2006.
Arnold Schwarzenegger and Bruce Willis were at the Rocky premiere in 2006
The original won three Oscars in 1977 - for best picture, director and editor - and it was up for a further seven awards, including best actor and screenplay for Stallone himself.
He was only the third person to be nominated for acting and writing in the same year, following Charlie Chaplin for The Great Dictator (1940) and Orson Welles for Citizen Kane (1941).
Today, the star waxes lyrical about British film-making, saying his favourite British director is David Lean, whose credits include Lawrence of Arabia.
As for actors, "Peter O'Toole, to me, is the guy" he says. "When I saw him in [historical drama] The Lion in Winter I lost my mind.
"I've seen that movie so much that my wife says 'if you do it again I'm going to stab you'," he jokes.
Stallone cites actor Peter O'Toole as one of his heroes
He says the British film industry's strength is in "intellectual endeavour", rather than relying on "action and physicality to get the most bangs for your buck", as he does in Rambo.
American movies can be "incredibly stupid and I'll be the first one to say it," he says.
"You're scratching your head, saying 'how did this crap get made? This is really moronic'."
He is self-deprecating about his own talents, and says he has found his niche.
"I've been identified with a certain kind of physicality and so for me to expect to be Daniel Day-Lewis or go into Russell Crowe land would be futile.
"It took me many years to figure out that you can't do everything, you got specialities, and you got things you look a total fool doing."
He thinks Britain has "the best actors in the world"
And he is aware that, as an older actor running around the jungle like a man in his 20s, he faces ageism.
"Of course you're fighting ageism - 78% of people in America are baby boomers, and they control 90% of the wealth, yet we don't make films for them.
"The average age for people seeing this film was 25. It's like 'let's go back and see what Grandpa used to do'."
But, despite all the hardships involved in making the movie, he says he would not have missed it for the world.
"I couldn't ask for a more harsh but more interesting experience," he says with a smile.