A Piece of Cake
This is an autobiographical account of Dahl's time as a fighter pilot in World War II, particularly the details of how Dahl was injured and eventually forced to leave the Mediterranean arena. The original version of the story was written for C. S. Forester so that he could get the gist of Dahl's story and rewrite it in his own words. However, Forester was so impressed by the story (Dahl at the time did not believe himself to be anything approaching an accomplished writer) that he sent it straight off to his agent who had it published (as "Shot Down Over Libya") in the Saturday Evening Post, thereby kick-starting Dahl's writing career.
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