Scarlett Johansson plays Black Widow in Marvel's Avengers: Age Of Ultron.
It might be just the second Avengers movie, but there are other numbers at play here. It's Robert Downey jnr's fifth film appearance as Iron Man, the fourth for Chris Evans as Captain America and Chris Hemsworth as Thor. It's hard to put a number on Samuel L. Jackson's turns as S.H.I.E.L.D boss Nick Fury, as he's cameoed all over the Marvel Cinematic Universe (MCU).
Also with yet more notches in their belts are Scarlett Johansson as Black Widow, Mark Ruffalo as Hulk, Jeremy Renner as Hawkeye and Tom Hiddleston as Loki.
But the real number that is hanging over the highly-anticipated superhero movie is 1.5 billion. That's how much in US dollars 2012's previous Avengers movie made. It was the third biggest movie of all time after Avatar and Titanic.
Given Marvel's pre-eminent place in pop culture, the question will be: Can Ultron outdo its predecessor? For fans, the question will be: What will I see here I haven't already seen in eight previous Avengers-related movies? And can director-writer Joss Whedon, who has said this will be his last Avengers movie, top the spectacle of last time?
The last time audiences witnessed the comic book icons assemble to fight evil was to fight the Battle of New York against Loki and his Chitauri Army.
Read more:
• Scarlett Johansson centre stage for final Avengers: Age of Ultron trailer
• Two new superheroes assemble for Avengers: Age of Ultron trailer
This time they've re-teamed to stop Ultron, a robot created by Tony Stark to help defend Earth but whose massive Artificial Intelligence has made it decide it would rather eradicate humanity.
The lethal power of Ultron is the ability to access all things technological, including the internet, and use these tools as a weapon.
Avengers: Age Of Ultron features on the cover of this week's TimeOut:
The technological theme comes up as the cast assemble to talk about the film at the Disney Studios in Burbank before its world premiere this week.
Ruffalo: "It's interesting that Elon Musk and Stephen Hawking came out a month ago saying that we should stop the unfettered technological revolution into Artificial Intelligence because they believe once we get into A.I. and weaponry, that could be the end of the world, or the end of mankind. It's interesting that this movie deals so much with that same question."
Renner: "I think technology is a really beautiful thing, but the terrifying part is that it grows exponentially faster than what we can really grab on to as humans. Basically, as soon as an android is running for president, I'm out of here."
Budgeted at a reported US$250 million ($334 million), the Ultron shoot headed to South Korea, the Aosta Valley in northern Italy and South Africa. Johannesburg provides the backdrop for one of the biggest action sequences in the film.
Though the locations are real, there is still much use of green screen, particularly in the action scenes.
Says Renner: "Sometimes they'll use real guys in those scenes and then they wipe them out digitally, so when it comes to me firing at robots or stabbing someone, it helps to have a bit of reference, but of course most of the time you're using your imagination."
Ultron, like its predecessor, is infused with humour. In this case, the bantering between the characters seems natural, as if Whedon allowed them to improvise. Hemsworth quickly dismisses that rumour.
"The truth is that Joss' script is the Bible. If you have something better you can attempt to bring to the tape, you can, but personally I just followed what was on the page. Joss wanted to make Thor funnier and more relatable, and got rid of the kingly God aspect because it's very easy for that to make him distant from the audience."
One of the subplots is a romantic relationship developing between Hulk and Black Widow.
Ruffalo: "To be honest, I didn't understand why these two would be together, so I met with Joss because I have to have everything explained to me, thoroughly. But as both these characters have experienced a lot of trauma and are kind of wounded, they have a connection."
Johansson: "The character arcs are interesting. Of course, the visuals are spectacular but that's not all it is, and it's exciting to be a part of a genre film that's good, that's smart and progressive. For me, career-wise, it's been wonderful to make a movie that people are rooting for, that they want to see succeed," she says. "As actors, we don't always have that luxury."
Hemsworth isn't the least surprised about the immense popularity of the franchise.
"It's storytelling, isn't it? This world is a heightened reality, and stories about heroes, justice and injustice, capture the imaginations of kids and adults. We can't help but get swept up in it, myself included. I certainly feel like a fan of this phenomenon."
And this many Marvel movies down the line, the stars say they are still having fun pretending to save the world more one time.
Hemsworth: "It felt like a bunch of old friends catching up."
In illustrating the atmosphere on set, he offers, "Joss Whedon would sometimes have to tell us to shut up and focus."
Chris Evans: "Well, it's a superhero movie and you're playing larger-than-life characters, so you're going to have fun. This time around it was like being in summer camp."
The villain and new stars of Age of Ultron talk about bringing their comic book characters to life on the big screen.
James Spader stars as Ultron, the villainous android our to rid the earth of humanity.
Spader may have played his share of baddies and eccentrics in his career but Ultron offered something new: "I have never worn a cape in a film and this is the first."
The Blacklist star hasn't dabbled much in the world of special effects.
"Prior to our film, and I'm not entirely sure of this, but if you were a computer generated animated character like Ultron your physicality would be captured in the motion-capture stage after principal photography. But for this I was wearing a fractal suit. Depending on what stage of Ultron we were filming, there was a big head rig at one point that had circular headlights with cameras in it that was recording my face," he explains.
Despite the hi-tech role, he isn't much of a gadget guy himself
"I'm old fashioned, maybe even archaic. Maybe I am just left behind a little bit, but because I'm a smoker I can relate to addictions and addictive personalities because I am somewhat obsessive-compulsive. And to me, technology is addictive in many ways. I remember when everyone starting having two or three televisions in their house, and what were the ramifications of that? Entire generations were formed sitting front of a TV screen. Well, now that's quadrupled."
And as for going from some of the biggest television shows of recent years to what's likely to be the biggest movie of 2015 ...
"TV has exploded and people don't go to the movies as much. It's only natural that it would lead towards things like superheroes and comic book movies. You have to deliver a lot of bang if you want people to come to see your movie."
Not to be confused with the character from the 2014 movie, X-Men: Days of Future Past, this incarnation of Quicksilver is a newly recruited Avenger who hails from an Eastern European country, Sokovia.
Quicksilver grew up with his sister, Wanda Maximoff/Scarlet Witch; these mysterious siblings raised each other after their parents abandoned them.
Quicksilver can move at superhuman speed. "For the most part I'm running really fast and nudging someone with my elbow so you have to put your trust in the fact it will look good," he says.
"I'd love to have Quicksilver's superpowers. It'd be great for travelling and getting across town quickly to avoid the LA traffic."
"I was really flattered to get the call from Joss Whedon and that he even thought of me for the role was amazing. I feel like you're in really good hands with Marvel because they bring their legacy to life and they want to see you give justice to the roles in the right way."
Wanda's telepathic powers enable to her receive messages from parallel universes, past, future or present.
"Everyone else is doing martial arts and I felt like the stupidest person in comparison to the others. At least Aaron is running but I'm just pretending to have a ball of energy in my palms and I'm throwing it at things that aren't there," she laughs. "Joss kept saying, 'I swear you're going to look cool.' So I had to have faith in him."
How is it joining the Marvel universe?
"I got a taste of it when I went to Comic-Con and it was a bit overwhelming. There were 10,000 people screaming at you. After that I was a wreck; it was wonderful but scary."
"I'm such a fan of the Marvel movies but I have to admit I was uncomfortable watching the parts I was in.
"I think if I had Wanda's powers, I probably wouldn't use them. I feel like it would be rude to manipulate people's minds," she says. "That is some bad territory I wouldn't want to get into."
Bettany voiced J.A.R.V.I.S., Tony Stark's A.I. buddy in previous films and is in the rare position of having played two characters in the Marvel franchise. Now he gets to step out of the sound booth and join the rest of the cast.
"I got to finally be on set with these people I'd been working with for 10 years but never met. It was fun. It's rewarding to be with really talented, creative people, even though it meant I had to go to the gym and actually had to turn up at press junkets," he says.
Vision is a key Avenger in the comic books, an artificial life form that is powerful but at the same time naive. "He's a complex and fun character to play."
Bettany is no tech-head. "I think we are inescapably attached to [technology] and the human evolution and the evolution of machinery is one now. I am the least technical person in the world besides my wife," he laughs. "And besides James Spader."
Watch the trailer for Avengers: Age Of Ultron:
What: Avengers: Age of Ultron
When: Opens at cinemas on Thursday April 23
- TimeOut
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