This is Ridley Scott’s 2003 director’s cut of the sci-fi classic, which hardly needed improvement back in 1979, when it had its world premiere at SIFF. (That’s right, its world premiere! Respect.) Here’s what’s interesting 27 years 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.” (R) BRIAN MILLER.

Fri., April 11, 11:59 p.m.; Sat., April 12, 11:59 p.m., 2008