It says something about a documentary when you suddenly find yourself, several times, shouting "FUCK YOU" at the screen. For me, that moment came near the end of Amy Berg's blistering and stunning West of Memphis, the most provocative retelling yet of two 20-year-old tragedies: the murders of three young boys in Arkansas and the rush to condemn, and keep locked away, the three innocent teens who rose to fame as the West Memphis Three. by Denis C. Theriault