Struggling to keep their lives and marriage together after the loss of their toddler son, a novelist (Milo Ventimiglia) and his wife (Sarah Shahi) are ready to end their retreat at a remote country house. On their last night, however, a panicked young woman (Sara Paxton) hammers on their door with a tale of being stalked by gas-masked intruders...and it turns out to be no mere fiction. Disquieting opus co-stars William Mapother, Oz Kalvan. 90 min. Widescreen; Soundtrack: English Dolby Digital 5.1; audio commentary. Also includes a Blu-ray 3D that requires a 3D television, a 3D Blu-ray player, and special glasses to reproduce the original theatrical experience. Three-disc set.