“The Day the Earth Stood Still” is 20th Century Fox’s contemporary reinvention of its 1951 classic. The film updates the Cold War themes of nuclear warfare, to the more modern concerns of man against nature, as well as man’s generally violent nature against one another. Keanu Reeves portrays Klaatu, an alien whose arrival on our planet triggers a global upheaval. As governments and scientists race to unravel the mystery behind the visitor’s appearance, a woman (Jennifer Connelly) and her young stepson get caught up in his mission – and come to understand the ramifications of his being a self-described “friend to the Earth.”