“Dark Windows” (**1/2 out of four) was a sporadically effective horror psychodrama about four teenagers (Anna Bullard, Rory Alexander, Annie Hamilton, and Grace Binford Sheene) who are all involved in a devastating car crash; when one dies, the surviving members all go on a weekend getaway where they are besieged and stalked by someone who may or may not be one of the deceased girl’s family members who blames them for the accident. Good performances and some chilling and dark irony regarding PSTD and survivor’s guilt elevates this a cut above most of its genre but is eventually dwarfed by film’s routine framework and story. Not all that different actually from “I Know What You Did Last Summer.”