“Countdown to Zero” opens with an image that terrifies us, though we can’t necessarily say why. By the time this unsettling documentary is over, we know the reason and we are even more frightened.
That first image is of enormous roiling clouds of the blackest black smoke, smoke that feels particularly menacing even before we realize it is the product of a nuclear bomb. “Countdown to Zero” is both a comprehensive look at the many ways we are all in terrible danger from the world’s 23,000 nuclear weapons and an understandably desperate plea to cut that total to zero.
As directed by the gifted Lucy Walker, whose previous work includes “Devil’s Playground” and ” Blindsight,” “Countdown to Zero” scares us good and proper, and not just because of its description of the way a nuclear blast would make things hotter than the surface of the sun, vaporizing everything in its path, even the upper crust of the Earth.
Walker adroitly mixes extensive newsreel footage, lively graphics and talking-head interviews with dozens of people, from scientists to think tank folks to world leaders such as Mikhail Gorbachev, Jimmy Carter, Tony Blair and Pervez Musharraf.
The most memorable words from a politician, however, come from a 1961 speech to the U.N. by President John F. Kennedy, words that are used as a recurring motif throughout the film.
“Every man, woman and child lives under a nuclear sword of Damocles,” Kennedy said, “hanging by the slenderest of threads, capable of being cut at any moment by accident or miscalculation or by madness. The weapons of war must be abolished before they abolish us.”