Jody and her family have arrived in the Bahamas. Here they'll get the chance to visit Little Bahama Bank - a dolphin study group run by friends of Craig and Gina. Jody can't wait to see some Atlantic spotted dolphins - even go swimming with them if she can. But a party of rowdy teenagers have docked near Dolphin Dreamer, and Brittany is intent on befriending them - much to everyone's disapproval! But then Jody hears the rumours about a sunken treasure ship nearby that has never been found. Whoever does find the long-lost Elvira will find centuries-old treasure and a small fortune! Jody wonders whether she and the rest of the crew of Dolphin Dreamer could be the ones to succeed. The trouble is, a certain obnoxious gang are wondering the very same thing . . .