First broadcast on 15 June 1983. Featuring Peter Cook as King Richard III.
Edmund, the mostly forgotten son of Richard Duke of York, oversleeps and arrives late for the Battle of Bosworth.
He's supposed to be fighting on side of the Plantaganets, but due to sheer incompetence and a rather rash reaction to Richard III taking his horse, he chops off the near-victorious King's head. Then he saves the life of Henry Tudor, leader of the opposing army.
Now his father is King and he is Duke of Edinburgh, Edmund wants to be taken more seriously. Having toyed with the idea of calling himself The Black Vegetable, he settles for Baldrick's suggestion, the name The Black Adder.