Double-Booked

In 1975, Émile Ajar won the Prix Goncourt for his novel The Life Before Us. The French literary prize is awarded only once to each author, so Ajar could not be recognized again.

Or so you’d think. It turned out that Ajar was a pen name of Romain Gary, who had already won the prize in 1956.

Gary/Ajar remains the only author to win the medal twice.