US Navy frogmen cut into a sunken WWII Navy ship to retrieve documents from a vault. And spot a white-haired girl(!) at the sea bottom. When she's brought aboard, she turns blue from suffocation - because she has gills. With regular dips in the ocean, she falls for Chris and learns some English. Her origin is a mystery. As a storm kicks up and the wreck teeters, Chris asks Dolphin to retrieve the documents, but the wreck slips into the abyss. Still, she surfaces smiling. With the mission complete, they'll return to land. Dolphin can't go, and dives overboard - into her world.; Aquaman helps Aqualad, a rejected child from Atlantis, to overcome his fear of fish. Aquaman adopts Aqualad as his sidekick.