Ridley Scott’s 1979 sci-fi classic Alien had its world premiere at SIFF. (That’s right, its world premiere! Respect.) Here’s what’s interesting three decades later: AIDS and ebola and SARS have given a whole new mortal resonance to Sigourney Weaver’s (disregarded) concerns about quarantine and infection. The bickering, class-divided shipmates reflect the movie’s origins in Thatcherite England. They’re fractious proles in the service of a corporate overlord whose computer proclaims, “All other considerations secondary. Crew expendable.” It’s paired with James Cameron’s 1986 sequel, a great action movie with far less dread, in which space Marine Bill Paxton memorably cries, “Game over, man!” Aliens is a showdown between mothers: Weaver’s Ripley, returning to the now-colonized planet where she battled the lone alien before, versus the alien queen and her burgeoning brood of acid-fanged, rip-ya-apart, double-jawed spawn. Call theater for showtimes. (R) BRIAN MILLER

Feb. 4-9, 2011