The cleverness of Levan Gabriadze's little creeper for the chat-room set, Unfriended, will probably be lost on those whose primary means of interaction is NOT social media. The film assumes the viewer understands the dynamic and appeal of Facebook, instant messaging and webcams and builds on that foundation an intermittently entertaining teen revenge flick that outside of social media's cyber-bubble would make no sense at all -- not that there is much sense even for cyber pros. A group of five high school friends (Shelley Hennig, Matthew Bohrer, Renee Olstead, Wil Peltz, and Jacob Wysocki) convene one evening and are joined by a mysterious, avatar-less lurker using the web address of a dead friend (Heather Sossamon). The lurker has targeted our charmingly jaded and multitasking quintet because they were responsible for posting a shaming video of their drunk, butt-hurt friend. The video was so much the talk of Fresno that the unlucky girl ended up shooting herself in the head -- on camera, of course. That too was posted online. The film delivers a bit of a primer on debugging and blocking pesky trolls -- even if these measures come to naught -- and the little nimrods are picked off one by one.