Three old friends (Kate Bosworth, Katie Aselton, Lake Bell) go camping on a remote island off the coast of Maine and are hunted by a pair of gun-toting army veterans. Aselton directed and came up with the story—sort of a feminist Deliverance—which was then turned into a script by her husband, indie icon Mark Duplass. The first quarter of the movie, unearthing an old grudge between two of the women, is contrived and perfunctory, a weak variation on the low-budget talkathons Duplass writes and directs with his brother, Jay (Baghead, The Puffy Chair). But once the survival story kicks in this turns into a pretty good exploitation flick