Ridley Scott’s Alien prequel, Prometheus, has practically none of the 1979 original’s visceral punch (for once I can use that adjective literally!), but also none of its dumb false scares or stupefying stretches in which characters on the verge of being skewered by a giant black monster with a glistening ovoid helmet-head search the bowels of a spaceship for a remarkably uninteresting cat. It’s a different sort of experience: a stately, somewhat plodding but endurable science-fiction saga that opens with the dawn of life on Earth and closes with mad carnage and a mystery even more troubling than how we humans got here. Along the way, I thought of 2001, The Thing (Hawks’ and Carpenter’s), and all those fifties sci-fi pictures that ended with “Keep watching the skies!” or a quivering “?” I thought of Lawrence of Arabia, mostly because the movie’s requisite robot-with-a-secret, David (Michael Fassbender), watches David Lean’s epic over and over and picks up Peter O’Toole’s pansexual wonderment as well as excellent posture. I thought of how nice it was to watch a Ridley Scott picture with no epic battle scenes for him to screw up. Scott might be the most overrated director alive, but he’s decent at slower tempos.