Uther covets Igrayne, wife of the Duke of Cornwall. Merlin helps him satisfy his lust, and, well, the seed of the heroic tragedy of the Arthurian tale is planted in her womb.
One of these days, I'll do a breakdown of this movie and highlight some of the interesting elements. Not today, though. For now, let's just watch and enjoy. Well... I will make one small bit of commentary. This scene here, more than any other I've ever seen, is what chivalry and honor are all about:
Both Arthur and Uryens exemplify the best qualities of knighthood here. Uryens accuses Arthur of subverting the chivalric code by demanding a knight swear faith to a squire. Arthur realizes he's right. He takes a leap of faith and hands Excalibur over to his enemy. He is literally betting his life on Uryens's sense of honor. And Uryens, to his credit, resists the temptation to take the sword and lop Arthur's head off. His conscience compels him to knight Arthur. The conflict is resolved, the two factions of knights are united, and they all set out to quell the land and bring peace and prosperity to the people.
Both men resisted temptation, humbled themselves, and did the honorable thing. And, in time, the whole land reaped the benefits.
If only all men were so knightly.