Hey, history lovers. I'm Mike Rosenwald with Retropod, a show about the past, rediscovered.

Adolf Hitler's march across Europe, his slaughter of six million Jews, his attempt to take over the continent and maybe the world, was one of civilization's most horrifying moments.

Now, imagine for a moment how it could have been so much worse.

Imagine Hitler with a nuclear bomb.

Today, let's remember the forgotten man who made sure it didn't happen.

His name was Joachim Runeberg. He was born in 1919 to a prominent Norwegian family.

When he was in his early 20s, Germany invaded Norway.

Ronneberg knew he had to do something.

He fled to Britain aboard a fishing boat and linked up with the Special Operation Executive,

a wartime espionage unit that British Prime Minister Winston Churchill called his Ministry of Ungentlely Warfare.

There, Roneberg studied the dark arts of sabotage, including how to lay a bomb, fire a weapon

and kill a man with his bare hands. He became very good at these skills, so good that he was appointed to lead a unit

that undertook some of the scariest, most crucial undercover operations of the entire war,

like the mission to blow up Hitler's nuclear ambitions. It was early 1943.

Allied forces discovered that the Nazis were increasing cold water production at an industrial

facility in southern Norway.

The plant was already the world's leading commercial supplier of heavy water.

A key ingredient German scientists were

using to produce weapons-grade plutonium for an atomic bomb.

Ronneberg's mission was simple and frightening. Destroy the plant. Was he scared? No, no, he was not.

We didn't think about whether it was dangerous or not, he once told Britain's telegraph newspaper.

You concentrated on the job and not on the wrists.

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