What drew you to this story?

Reading these guys’ memoirs and learning what they endured in order to take down this atomic facility really got me, not only with the fighting, but this epic struggle with nature, as well. They sometimes cross-country skied a marathon distance every day for a week to escape, or to hunt reindeer, or just to get out of the way of a blizzard.

Who were these guys, exactly?

They came from every walk of life. Very few of them had military training. A lot of them were from the area. It’s like Red Dawn, that ’80s movie with Patrick Swayze, about every boyhood dream: The enemy comes in, takes over, then a ragtag group of citizens beats them back.

Tell us about the training.

These guys trained up to 18 hours a day, doing calisthenics, running, gymnastics, wrestling, obstacle courses, hand-to-hand combat, and weapons training. Then the focus was on getting these guys to be supertough, and this meant largely living outdoors, 35-mile hikes with 40-pound packs, crossing rivers, and climbing mountains for weeks at a time. Finally, they were sent to what was called “finishing school,” which was a kind of Tough Mudder-like competition in which the first to get to and “blow up” a fake train station won.

What made it so hard to reach the actual nuclear facility?

It’s a fortress on an icy crag of rock in the middle of nowhere. They had to parachute in and survive for months.

Then in the middle of the night in a snowstorm, they had to climb an icy 600-foot cliff, somehow bypass elite guards, and blow it up. But the Germans never expected it. 

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