A baby dolphin has become trapped while playing in a shipwreck. Launch LEGO Friends Stephanie's cool submarine into Heartlake City Bay and embark on a dolphin rescue! But she's not the only one buzzing around the wreck. LEGO Friends Kacey is on a sea scooter looking for the treasure chest to keep for herself. But there's also a mysterious treasure map to find on this LEGO rescue mission. Help Stephanie free the dolphin, discover the map and go on a LEGO treasure hunt to reach the chest before Kacey gets there first!