Michael Fassbender stars in Assassin's Creed. Photo / Getty
It's easy to see a staggering amount of work has gone into creating the epic battle sequences peppered throughout new blockbuster movie Assassin's Creed.
But producer and lead actor Michael Fassbender has revealed to news.com.au the one stipulation that made production just that bit more finicky.
"It was very important for us to shoot the action sequences with the stuntmen at real live locations and not do it in a carpark or a studio with a green screen," the 39-year-old star explained.
"We wanted it to be old-school and we felt that would set it apart from a lot of films - especially nowadays, when it's so much about CGI [computer-generated imagery] and special effects."
In the movie adaptation of the wildly popular video game franchise by the same name, Fassbender plays Callum Lynch, a prisoner on death row who involuntarily becomes wrapped up in a centuries-old war over the very existence of free will.
Through a genetic memory program - driven by Dr Sophia Rikken (Marion Cotillard) - he explores the life of his ancestor Aguilar, and discovers he is a descendant of the secret Assassins society.
It's that science which attracted Fassbender to the story, which spent years in the production phase.
"I just loved the concept of DNA memory, the possibility that what we call instinct or sixth sense is actually the knowledge and experience and life of our ancestors that we hold in our DNA," he said.
"I thought that seemed really plausible - it's something that's being investigated really seriously by scientists."
It's a risky venture, transforming multibillion-dollar games into movies, considering the history of ridiculed attempts - but that's not something that concerned Cotillard when she signed up for the project.
"I didn't really know about the curse of video games and movies, so the first thing that drives me [to a movie] is going to be the story ... in this case, knowing I'd be teaming up with Justin [Kurzel, the director] and Michael was very exciting," she told news.com.au
"And I read the script, and thought it was fascinating ... I'd read books about scientists and how it can affect who you are today and so I really do believe that we carry this in us."
When Fassbender's character Lynch heads back in time as Aguilar, he teams up with fellow Assassin, Maria, who is played by Greek-born French actress Ariane Labed.
But it was very nearly his real-life girlfriend, Alicia Vikander, by his side. "With Alicia, she's in high demand - everyone wants her in their films," Fassbender gushed.
"We were looking at the possibility [of casting her as Maria].
"But I've got to say, I'm so thrilled we got Ariane Labed - she's one of my favourite things in the movie."
Assassin's Creed is in cinemas from January 1, 2017.