An underseen classic, Fail-Safe is based on a very similar story (though not the same book) as filmcritic.com's #1 movie, Dr. Strangelove. (In fact, Kubrick sued Sidney Lumet and co. over the similarities between the films, before either ever came out.) But Fail-Safe plays it straight, to equally powerful effect: An accident sends a bombing team on its way to Moscow, and the U.S. wrestles with what to do when it can't be recalled. Walter Matthau is a scene stealer, playing a rare serious role as a civilian advisor to the Pentagon who advocates all-out war. Jaw-dropping and tense, despite some rough production values.