The invasion begins at night, with German cruisers slipping into harbor, and soon the Nazis occupy all of Norway. They station soldiers throughout the country. They institute martial rule. And at Vemork, an industrial fortress high above a dizzying gorge, they gain access to an essential ingredient for the weapon that could end World War II: Hitler's very own nuclear bomb.

When the Allies discover the plans for the bomb, they agree Vemork must be destroyed. But after a British operation fails to stop the Nazis' deadly designs, the task falls to a band of young Norwegian commandos. Armed with little more than skis, explosives, and great courage, they will survive months in the snowy wilderness, elude a huge manhunt, and execute two dangerous missions. The result? The greatest act of sabotage in all of World War II.