Arthur Pendragon, the Once and Future King of Britain, is awake and on a world tour that lands him in London. At the same time, Macbeth, the King of Scotland and Father of the King Thereafter, is awaiting a magical prize to drop from a gate in time and space. Turns out that the prize is Arthur and Griff. Bummer. But the search is on for Excalibur, which may in fact be in the Brooklyn Gardens. Which king is worthy to wield the legendary blade?