Under the sea, a dorky dolphin is sad that no one has shown up to his birthday party. He pretends to have a party using the seashells on the ocean floor as his guests. When he accidentally uses an occupied shell as his puppet, he befriends a happy clam and a goofy hermit crab. When a beautiful shark swims by, the dolphin is in love, but the shellfish are terrified and scuttle away. A fierce storm begins and the dolphin and his new crush seek shelter in an abandoned pirate ship. Also seeking shelter from the storm, a little squirrelfish swims in and is trapped when a large old box tips over on to her tail. When the sea creatures try to save her, they learn from the smart dolphin that the old box is actually a treasure chest. Greed takes over as the seas creatures fight over necklaces, bracelets, gold coins, and finally a royal crown. Friendships are destroyed. Fish sink to the bottom from the weight of the necklaces and bracelets they are wearing and the gold coins they have eaten. The kind-hearted rabbitfish convinces the others that they are better off without the treasure. The sea creatures return their finds to the treasure chest. However, the snobby starfish is not convinced and dives into the treasure chest to get it all. A huge wave slams the treasure chest shut, trapping the starfish.