Princess Guinevere pines for a sea view, King Arthur and Merlin seek out King Canute for advice. They catapult the famous 'round table' into the sea to block the Penzance Plug Hole. The sea rises – and keeps rising until Guinevere's tower is in danger of being engulfed. Will sharped-toothed sharks, a giant sea monster and a dissolute Scottish Pirate prevent the King from draining the Plug Hole and rescuing his beloved from a watery grave and wet hair?