In the dead of night, the merchant ship, the SS electric, weighs anchor and slips silently

from port in Liverpool. It's the 2nd of July, 1940, and Britain is at war with Germany.

The ship is packed with 2,600 men, more than twice the number it's designed to accommodate.

Half are immigrants and refugees who came to the UK to escape the fascists on the continent.

They've now been labelled enemy aliens by a paranoid British government

and a headed for an internment camp in case they turn out to be Nazi spies.

The other half are German and Italian prisoners of war. In other words, the very fascists the

immigrants are fleeing from. The men have a perilous crossing ahead of them. They're destined for

Canada, but Nazi U-boats are harassing the North Atlantic. Just days earlier, the electric

sister ship, the Arandora Star, was torpedoed, killing more than half of those on board.

And now, on the electric, every groan of the hull brings cries of terror.

One of the internees on board is the brilliant atomic physicist, Klaus Fuchs.

Another is Hans Karler, top spy recruiter for the Soviet Union.

From the BBC World Service, I'm Rosarellis, and this is Season 2 of the Bomb.

Episode 2. A Split Life.

Klaus Fuchs's voyage on the SS-Ectric is a cruel twist of fate.

Since his arrival in the UK, he's enjoyed peace, stability, and life as a flourishing academic

among some of the brightest minds in mass and physics.

Having fled Nazi persecution in 1934, he secured a place to study his PhD at Bristol University.

For men like Fuchs, these are exciting times.

In the 1920s and 30s, the field of quantum mechanics and nuclear physics was just emerging.

It was the most exciting discipline to study, and it attracted the best minds in physics from

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