Alexander Weissberg-Cybulski

Alexander Weissberg-Cybulski (born October 8, 1901 – April 4, 1964[1]) was a Polish-Austrian physicist, writer and businessman of Jewish descent.

It was this relationship with Bukharin that was later to become central to the regime's attempt to frame Weissberg as part of a conspiracy to assassinate Stalin.

Koestler's preface explains how the advocacy of fellow physicist Albert Einstein was instrumental in securing the Nazi release of Weissberg.

During World War II he changed his surname to Weissberg-Cybulski, taking the name of Graf Cybulski, his wife's first husband.

This book tells the story of Joel Brand and examines the working of the Jewish underground movement in Hungary and other places during the Second World War.