There have been conflicting reports as to whether director Ridley Scott's latest film, "Prometheus," is a prequel to his landmark space thriller "Alien." The answer is clear once you see the film.

Either way, the tendency is to compare the movies because of their similar storylines and structure. And when the films are compared, "Prometheus" begins to lose a little of its cinematic might.

Scott's 1979 "Alien" set new standards for space terror through an almost endless onslaught of tension-filled moments. The tension escalated because of the confined setting of the small spacecraft that had become infected by a terrifying creature.

"Prometheus" also deals with a group of space travelers who, through their quest for knowledge -- and some backing from the same kind of evil corporate world that reared its ugly head in "Alien" -- find themselves in a battle with an alien species. The big difference is their battle isn't confined to a spaceship, but takes place on a distant world.

Scott again turns to strong female characters to be the heart and soul of his story. In "Alien," it was Sigourney Weaver while in "Prometheus," Scott casts Noomi Rapace, of "The Girl With the Dragon Tattoo" fame, to be the heart of the expedition. She's the scientist who decodes ancient messages telling humans where to find the alien race that millennia ago walked the Earth. Charlize Theron's the corporate soul, as the leader of the expedition who's hiding a very secret agenda.

"Prometheus" is a feast for the eyes as Scott elevates the visuals to a new sci-fi high. From the holographic images on the ship to the massive beehive-like structures, the film is glorious in design.

The casting is nearly as perfect, with Rapace's passionate performance balanced by the cold and methodical thinking of Theron's character. There are a few minor flaws: Idris Elba, who plays the ship's captain, is underused, and Guy Pearce works under mounds of makeup as the mission's rich benefactor. There's no reason a younger actor had to be cast and put through such extensive makeup.

It's no coincidence Scott selected "Prometheus" as the name of his film. In Greek mythology, Prometheus was a titan who has come to represent the struggles of mankind, particularly in the search for scientific knowledge and the consequences that can come from going too far.

Scott falls prey to such an extended reach, as "Prometheus" suffers from the advances in filmmaking since "Alien." Shifting the action to a distant world eliminates the claustrophobic tension that made "Alien" so memorable. Instead, the film is filled with a bleak vastness that's interesting but not quite as compelling.

And then, there's the unkindest reach of all -- the obvious setup for a sequel. Such a blatant tactic leaves the film with a sense of being incomplete. Couple that with a slow beginning, and there are times when the plot of "Prometheus" feels like it's chained to a rock.

Still, Scott's titanic effort in "Prometheus" yields such a visual triumph that small flaws can be overlooked.

MOVIE REVIEW

"Prometheus," rated R for language, violence. Stars Noomi Rapace, Michael Fassbender, Charlize Theron, Idris Elba, Guy Pearce. Directed by Ridley Scott. Running time: 124 minutes. Grade: B+