Sir Ridley Scott has been talking up his Alien prequel, promising a "really nasty" 3D treat which he described as "the dark side of the moon".

The movie will be set in 2085, five years before the original, and will see the protagonists "first come across this thing on a planet called Zeta Reticuli". Scott teased to Screen International: "Were the aliens designed as a form of biological warfare? Or biology that would actually go in and clean up a planet?"

He added: "And it will ask who was that guy in the first film lying in a chair with his chest blown outwards when they first go into the giant spacecraft."

The 72-year-old director insisted his project will challenge James Cameron's Avatar in terms of 3D spectacle. He said: "Jim's raised the bar and I've got to jump to it. He's not going to get away with it."

Alien first thrilled cinemagoers in 1979, although Scott hasn't helmed a sci-fi film since 1982's Blade Runner. It's not certain whether he'll direct this latest outing for the Alien franchise, and word has it he may hand over control to Carl Erik Rinsch.

Other news sources say Scott's actually planning two prequels, although details are scarce. He did, though, tell MTV: "It'll be two. Prequel one and two, then Alien 1." ®