A kind of suicide hotline for a rogue-nuke world, “Countdown to Zero” boasts a cast of international superstars — Jimmy Carter, Mikhail Gorbachev, Pervez Musharraf, Tony Blair — and a convincing argument that the human race is on borrowed time: Given the number of nuclear weapons in existence, the ease with which they can be made, the eagerness of terrorists to possess them and a worldwide cluelessness about nuclear security, it’s only a matter of time before something terribly ugly happens. A politically urgent picture, it will also literally scare the breath out of what will certainly be a worldwide audience.

There’s a great deal of heroism exhibited alongside the craven stupidity of “Countdown to Zero,” but no subject comes off as heroically as one discredited Russian: Boris Yeltsin. Back in 1995, “Countdown” says, Americans fired a rocket meant to study the aurora borealis, but the launch was interpreted by Moscow as a U.S. attack. (Yeltsin’s people had been notified in advance, but the message got lost.) If the Russian leader hadn’t second-guessed his own people, nuclear warheads would have been headed toward American cities.

“He wasn’t drunk,” explains Joe Cirincione of the Ploughshares Fund, one of the several charismatic nuclear experts/activists who help make “Countdown to Zero” so informative. It’s a funny moment, sure, in a film that doesn’t avoid the occasional laugh. But the point is that, for one moment, the fate of the entire planet could be decided by one man who simply had his doubts. And not everyone is as sober or stable as Boris Yeltsin was, at least on one day in ’95.

Among helmer Lucy Walker’s credits are “The Devil’s Playground” and “Blindsight,” and “Countdown to Zero” is another example of highly creative documentary-making: Bouyed by Peter Golub’s score and several sturdy rock numbers (Pearl Jam contributed the closing-credits song, “The Fixer”), the film is built around terrific archival footage from dozens of sources. The near-operatic opening, narrated by actor Gary Oldman, uses reverse footage of the ’40s Los Alamos A-bomb tests, suggesting nostalgically that time might be turned back to a pre-nuclear world — and indicating, as well, that such a fantasy perspective has infected the entire issue of destructive nuclear power.

As put quite bluntly by Valerie Plame Wilson — the lone female and certainly most photogenic of “Countdown’s” talking heads — Al Qaeda wants the bomb, and has been actively seeking to make one. As put by President John F. Kennedy — in a speech to the U.N. used throughout the film for dramatic effect — a “sword of Damocles” has hung over every living person, because “accident, miscalculation or madness” might well cause a disastrous nuclear event.

Or one of the world’s existing 23,000 nukes might go off. Or some lunatic might get the bomb — a possibility made quite real via footage of the non-nuclear attacks in Madrid, Bali, London, Riyadh, Buenos Aires, Oklahoma City and, of course, New York. Imagine, the film suggests, if the terrorists had gone nuclear.

There are moments when “Countdown to Zero” seems to have bitten off more than it can chew — existing state nuclear arsenals seem to be a separate, if overlapping, consideration from terrorism. On the other hand, the looseness of security regarding Russia’s old nukes is a problem all around, so it’s hard to see where a film about one might end and a study of the other might begin.

One of “Countdown’s” masterstrokes is a man-on-the-street device by which people in multiple global cities speculate or comment on the world nuclear situation; another is the use of New Year’s Eve in Times Square, over which we hear an accelerating catalogue of calamities that would follow a single nuclear blast in a major city, and a litany of physiological horrors, social chaos and civil disintegration from which the world would never recover.

It certainly registers as a visceral way of scaring sense into people: Being a Participant Media production, “Countdown” emphasizes its interactive aspects and provides audiences with ways to enter the debate — information they will likely ingest, as soon as they can catch their breath.

Tech credits are tops, particular the immaculate images created by the film’s four cinematographers.

Countdown to Zero

  • Production: A Participant Media presentation in association with the World Security Institute. (International sales: Submarine, New York.) Produced by Lawrence Bender. Executive producers, Jeff Skoll, Diane Weyermann, Bruce Blair, Matt Brown. Co-producer, Lisa Remington.
  • Crew: Camera (color/B&W), Robert Chappell, Gary Clarke, Bryan Donnell, Nick Higgins; editors, Brad Fuller, Brian Johnson; music, Peter Golub; music supervisor, Matt Biffa; sound, Walker, Michael Boyle, Alexander Marshall, Evan McIntosh, Hashem Selph; supervising sound editors, Harry Cohen, Wylie Stateman; re-recording mixers, Michael Minkler, Tony Lamberti; visual effects supervisor, Forrest Heidel; visual effects, Panoptic; associate producer, Brennan Rees. Reviewed at Sundance Film Festival (Spotlight), Jan. 25, 2010. Running time: 90 MIN.
  • With: With: Jimmy Carter, Mikhail Gorbachev, Tony Blair, Valerie Plame Wilson, Joe Cirincione, Zbigniew Brzezinski, F.W. de Klerk, Pervez Musharraf. Narrator: Gary Oldman. (English, Persian, Mandarin, Russian, Urdu dialogue)