Penguin Blue is back, in a swashbuckling new adventure about pirates, treasure, and friendship! A pirate hat. A sunny day. Sailing the seven seas in search of treasure, Captain Blue and his friends are unexpectedly SUNK! But with a shipwreck to explore and a mysterious stranger on a desert island to meet, they might still find some treasure after all ... The fourth book from the award-winning, bestselling picture book star Rob Biddulph.