Deguelt gave up his studies to become a cabaret singer in Paris in the early 1950s. In 1956, he was the winner of the Grand Prix du Disque of the Académie Charles Cros. Following a period of military service in Algeria, Deguelt returned to France, and was offered the chance in 1960 to sing for Monaco in the fifth Eurovision Song Contest, held in London on 29 March. Deguelt's song "Ce soir-là" ("That Night") proved popular with the juries, finishing in third place of the 13 entrants.