After months of rumour, speculation, whispers, sort-of news and denials aplenty, 20th Century Fox has finally come out and announced via Twitter that Ridley Scott’s next stab at science fiction will be called Prometheus and that Noomi Rapace has signed on to star.

This is the point where you raise your eyebrows and wonder what happened to the long-gestating Alien prequel. Turns out, this is what that film evolved into. After a lot of development, Scott has decided to move away from the history of the Xenomorphs and make something original.

Talking with Deadline, Scott puts some flesh on those Twitter news bones: “While Alien was indeed the jumping off point for this project, out of the creative process evolved a new, grand mythology and universe in which this original story takes place. The keen fan will recognize strands of Alien’s DNA, so to speak, but the ideas tackled in this film are unique, large and provocative. I couldn't be more pleased to have found the singular tale I'd been searching for, and finally return to this genre that's so close to my heart.”

With Scott as the original driving force, Jon Spaihts wrote the first draft of the script, which he then worked on with former Lost show runner Damon Lindelof with the instruction to fire it off into brand new territory. "In a world flooded with prequels, sequels and reboots, I was incredibly struck by just how original Ridley's vision was for this movie,” says Lindelof. “It's daring, visceral and hopefully, the last thing anyone expects. When I sat in a movie theatre as a kid, feet raised off the floor for fear that something might grab my ankles, I never dreamed in my wildest imagination I would one day get to collaborate with the man responsible for it. Working alongside him has been nothing short of a dream come true."

Rapace, meanwhile, has long been a favourite of Scott, who was impressed by her work in the original version of The Girl with the Dragon Tattoo. She’ll play scientist Elizabeth Shaw, one of five main roles, with the other still to be cast. Deadline’s report mentions Angelina Jolie and Charlize Theron in consideration for the other big female role, named Vickers. Neither is a real surprise – Theron’s name has been bandied about before and Jolie is offered pretty much everything.

And here’s the kicker – Fox has also announced that the film will arrive on March 9, 2012. This thing is finally real, people. Even if it’s something very different now. Anyone wondering if we'll still get to see the origin of Alien's Space Jockey?