While there is little factual evidence to support the belief that there were three kings, the image has annually adorned cards, carols and nativity scenes. But only one passage in the Gospel of St Matthew, written 40 years after the birth of Christ, refers to the arrival of "wise men" - and there is no mention of numbers. The documentary demonstrates how the belief there were three kings was the result of over-fertile artistic imaginations loosely based on the Gospel.