The Müller File (en Inglés) - Scott Hamele

Peter makes a decision that will shape the rest of his life. He leaves Germany for England.

At Hatfield, he finds work in Britain's rapidly developing aircraft industry, bringing with him an engineer's precision, an immigrant's caution, and knowledge acquired inside one of Germany's most important aviation firms. England offers him professional opportunity, but acceptance comes slowly. To British officials, his abilities make him useful. His nationality makes him suspect.

Then he meets Evelyn Ashcombe.

An English publishing assistant with little interest in aircraft but an instinctive understanding of people, Evelyn sees something in the reserved German engineer that official files cannot record. Their friendship deepens as Europe moves toward war, forcing Peter to confront an increasingly difficult question: can a man choose where he belongs when governments insist that nationality determines loyalty?

By 1939, Britain and Germany are at war.

Peter has built a life in England, yet the country he has chosen cannot entirely forget the country printed on his papers. British intelligence watches him. German interests have not forgotten him. His specialized knowledge of aircraft design has become valuable to both sides, and the engineering experience that once promised him a future now places him in danger.

In 1940, fear of invasion sweeps Britain. German and Austrian nationals are classified, investigated, restricted, and, in many cases, interned as enemy aliens. Peter discovers that years of work, friendship, marriage, and demonstrated loyalty can be reduced by wartime necessity to a birthplace and a government file.

Separated from Evelyn and sent to the Isle of Man, Peter enters a world of guarded hotels, uncertain futures, and men whose individual histories have been compressed into the same dangerous label. Yet another threat is taking shape beyond the fences. Germany still understands the value of what Peter knows.

As Britain fights for survival, Peter finds himself caught between two nations: one he abandoned because of what it was becoming, and another he chose as home but which is no longer certain it can trust him.

His greatest secret is not where he came from.

It is what he knows.