Bug comes billed as a horror picture, but for awhile it plays like a very good stage play. I was surprised when I later learned that it was based on one. The 2006 film, directed by William Friedkin, is set in the Oklahoma desert, almost entirely as a motel inhabited by a lonely bar maid (Ashley Judd). Her dangerous ex-husband (Harry Connick Jr.) has just been released from prison and she has been receiving ominous phone calls. After partying one night with her girlfriend, she meets and is soon taken up with a strange young man (Michael Shannon). Then the infestation sets in. Like I said, Bug plays out very nicely for awhile, establishing mood and atmosphere alongside nice performances from Judd and Shannon. Then, as the horror elements set in, Bug takes a turn for the worse, becomes ludicrous, and is a letdown for the entire third act. Still, even as a disappointment, the first two-thirds are a success and it is a pleasure to watch Michael Shannon at work at his craft.