Get a taste of what awaits you in print from this compelling excerpt.

Twenty years ago this month, life in Pripyat came to a shuddering end. Before dawn on April 26, 1986, less than two miles (three kilometers) south of what was then a city of 50,000, the Chernobyl Nuclear Power Plant's number four reactor exploded. Thirty people died in the blast and fire or were exposed to lethal radiation. The destroyed hulk burned for ten days, contaminating tens of thousands of square miles in northern Ukraine, southern Belarus, and Russia's Bryansk region. It was the worst nuclear accident the world has ever seen.

The fallout, 400 times more radioactivity than was released at Hiroshima, drove a third of a million people from their homes and triggered an epidemic of thyroid cancer in children. Over the years, the economic losses—health and cleanup costs, compensation, lost productivity—have mounted into the hundreds of billions of dollars. As evidence of government bungling and secrecy emerged in its wake, Chernobyl (or Chornobyl, as it is now known in independent Ukraine) even sped the breakup of the Soviet Union.

Today the fiercely radioactive remnants of reactor four continue to smolder beneath the so-called sarcophagus, a decaying concrete-and-steel crypt, hastily built after the accident, that now threatens to collapse. Work is about to get under way on a replacement: an arched structure, the size of a stadium, that will slide over the sarcophagus and seal it off. With its completion the destroyed reactor will be out of sight. But for the region's people it will never be out of mind, as a slow-motion catastrophe continues to unfold.

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