Sir Cliff Richard was robbed of victory in the 1968 Eurovision Song Contest due to vote rigging by General Franco's fascist regime, a documentary claimed.
The British singer's tune Congratulations was beaten to the top spot by Spanish entrant Massiel to boost the country's international image, film-maker Montse Fernandez Vila said.
Sir Cliff's song had been a favourite with the judges during the competition held at the Royal Albert Hall, but lost out on the title by just one point following a last minute rally in votes for Spain.