Louis Dega was a prisoner in the French Guiana penitentiary of Devil's Island. He was convicted of fraud and counterfeiting and sentenced to fifteen years' imprisonment by France, where he became a companion of Henri Charrière for thirteen years. The two were first sent to a prison in Caen, France, until they embarked for South America in 1932. He had a younger brother named Joseph who tried to help Charrière escape from Barranquilla prison in Colombia. Dega and Papillon had previously met before embarking to South America, and made a deal in which Dega paid Papillon for protection. The two became best friends during their sentence.
Over thirty years after his escape, Charrière included Dega in his autobiography. Director Franklin J. Schaffner adapted the book to a movie in 1973, with Steve McQueen playing Papillon, and Dustin Hoffman playing Dega. Their exploits together were greatly dramatized in the film.