We’ve known for years that Ridley Scott has wanted to return “to where the alien creatures were first found and explain how they were created” for his Alien prequels, and bit by bit, he’s been expanding on what such an origin story would entail.
The film will be really tough, really nasty. It’s the dark side of the moon. We are talking about gods and engineers. Engineers of space. And were the aliens designed as a form of biological warfare? Or biology that would go in and clean up a planet?
These few sentences help clarify an earlier interview with Scott, in which he said:
It’s set in 2085, about 30 years before Sigourney [Weaver's character Ellen Ripley]. It’s fundamentally about going out to find out ‘Who the hell was that Space Jockey?’ The guy who was sitting in the chair in the alien vehicle — there was a giant fellow sitting in a seat on what looked to be either a piece of technology or an astronomer’s chair. … [The film] is about the discussion of terraforming — taking planets and planetoids and balls of earth and trying to terraform, seed them with the possibilities of future life.
In other words, the terraforming in some way results in the creation of the alien creatures, and the film will likely join a slew of other sci-fi films in demonstrating the consequences of playing God.
I’m still not sold on the prospect of explaining away the mystery of where the aliens came from as them being a “designed” species. To me, the idea that the aliens were a naturally-evolved form of extraterrestrial life that humans just happened upon was far more appealing (and terrifying), and I appreciated the series allowing me that interpretation. Finding out that humans were responsible for the creation of the aliens (if that is indeed what Scott is hinting at) would greatly diminish one of the central aspects of the series that I love.
Even so, hearing Scott describe the film as “really tough” and “really nasty” inspires me with hope, as does the confidence Scott evoked when acknowledging the high standards set by himself and James Cameron (Aliens). “Jim’s raised the bar and I’ve got to jump to it. He’s not going to get away with it.”