Join ocean explorer Sandy Fin and his best friend Lily in the third adventure in the hilarious middle grade series by Martin Stewart, illustrated in black and white. Nothing strange has happened in Portwhistle for - almost intolerably - nearly a fortnight. Sandy is itching for an adventure. Then he and Lily discover a map to the wreck of the Crooked Blade, a sunken galleon, rumoured to house mounds of gold and Blackbeard's silver-plated skull! Sandy and Lily set out to find it, but they are not the only ones. Sandy's arch enemy Tye Straker and his crew of pirate-obsessed pals, the Bucchanhiers, are hot on Sandy's scales. The map takes them through a series of maritime tests and puzzling clues; they must brave thunderous whirlpools, vampire squid and strange crop circles in seaweed, thwarting their opponents at every turn. Armed with Emile's latest inventions, can Sandy and Lily make it to the shipwreck first?.