Stars of the hit BBC drama series, Merlin, set off across Wales on an historical exploration called, The Real Merlin and Arthur.
You can see the efforts of Colin Morgan and Bradley James on the iPlayer until 5 December.
On the way they encounter enthusiasts and experts in Arthurian lore, and visit some of the most breathtaking landscapes in Wales.
During the three-day road trip they visit places linked with Arthur.
Among the key places are Mold library, home of the largest collection of Arthurian texts in Wales, where they meet Scott Lloyd, co-author of, The Keys to Avalon, and, Pendragon: The Origins of Arthur, to discuss their route as well as the world's enduring fascination with the legend.
They visit Llanuwchllyn, near Bala - thought by some to be Arthur's childhood home and they drive across Bwlch y Groes, the highest public road mountain pass in Wales, and the legendary resting place of a giant reputed to have been slain by King Arthur.
In Dinas Mawddwy, they meet local enthusiast Laurence Main (author of, King Arthur's Camlan - a Quest for Truth) who teaches them the art of dowsing, and brings them to the point where various "ley lines" converge on what he believes to be the location of Arthur's death after his final battle with the Mordred.
"We've spent eight months in Cardiff and we haven't seen any of Wales," says Colin. "So this is a chance for us to see the sights and hopefully find out who the real Arthur and Merlin were."