Billy Elliot's original title was 'Dancer', but when they took the film to the Cannes Film Festival, there was another film called
Dancer in the Dark (2000), which won the Palmes D'Or, prompting confusion; indeed, Universal Studios called the directors, producers and writer up and congratulated them. They then realized they had to change the name and settled ('rather lamely', joked the writer) on 'Billy Elliot'.