“It had been dormant for a while and we saw it on a shelf,” says screenwriter and producer Robert Orci, who - with writing partner Alex Kurtzman - adapted the film’s script from Scott Mitchell Rosenberg’s graphic novel. “We saw the title, 'Cowboys And Aliens', and we thought, 'why isn't this a movie?'”

Rosenberg’s concept had actually been kicking around Hollywood since 1997, until he published the story in comic book form in 2006 to speed the process along. It was only once Kurtzman and Orci - the team behind ‘Transformers’, ‘Mission: Impossible III’ and JJ Abrams’ ‘Star Trek’ reboot - got involved that the project started to pick up steam. They pitched it to Steven Spielberg, who in turn pitched it to Ron Howard. Both came onboard as producers.

“It was amazing,” says Orci. “We'd be in meetings where we were like, 'let's take a little bit from ‘E.T.’ and take a little bit from ‘Cocoon’, and a little bit from ‘The Missing…’ I think we would have paid to sit in a meeting like that with those guys. And this is the first time that Steven and Ron have worked together, the very first time.”

Director Jon Favreau soon became attached to the film, along with Daniel Craig and - in the biggest thrill yet for Kurtzman and Orci - Harrison Ford. “He gives you his opinion in a way that's both extremely respectful and also very aware of what the movie wants to be,” says Kurtzman. “It's never, 'I'm one of the most famous actors in history...' it's about, 'if we're going to embark on this endeavour together here's what I think we need to do to make this movie great.' And when someone like Harrison Ford is coming from that place, it's an invaluable resource.”

Despite the potential for cheese, Orci and Kurtzman were determined to tell the story of an alien invasion in the 1870s as a straight-down-the-line action thriller. Striking the right tone wasn’t easy.
“We started writing,” Orci says, “and we were like, 'now we know why it hasn't been made before.' It's hard!”

‘Cowboys & Aliens’ beams into cinemas this Thursday August 18.