When two US Navy frogmen, CPO Chris Landau and Seaman 1st Class Ben Harkey, investigated the sunken wreckage of the ship USS Arabesque, they discovered a beautiful young woman living within, obviously able to survive underwater without drowning. Brought aboard their own ship by Chris and Ben, the young woman was found to have gill-like slits in her neck and slight webbing between her fingers and toes. Chris named the mysterious woman "Dolphin".
As the next few days passed, it was discovered that, although Dolphin had fully developed lungs, she had to return to the water briefly every five or six hours, or risk suffocation and death. Chris fell in love with Dolphin and was heartbroken when she ultimately returned to the seas.
Dolphin was seen again as a member of a group gathered together by a being known only as the Immortal Man. As with the other heroes, Dolphin had accidentally stumbled across one of several ancient golden pyramids that were of supreme importance to the American Government. When it was learned that these pyramids were part of a monstrous plan by the villainous Vandal Savage to conquer the world, Dolphin and the other heroes, which included Animal Man, Congo Bill, Rick Flag, and Cave Carlson, destroyed the pyramids with the help of Superman and thwarted Savage's schemes.
When the Immortal Man suggested the heroes, named the Forgotten Heroes, remain together on a more permanent basis, Dolphin agreed. She remained with the team until their eventual break-up.
Dolphin has since acted as a solo adventurer, teaming up with her ex-teammates Animal Man and Sea Devil Dane Dorrance to stop dolphin killers from the Faroe Islands as well as teaming up on a Justice League Task Force led by Martian Manhunter into the Valley of Daal.
Recently, Dolphin had been captured by the evil Charybdis in his plot to capture both her and Aquaman to gain underwater powers. After defeating Charybdis with Aqualad's help, the three have remained together.
An Olympic-level swimmer with little knowledge of hand-to-hand combat, Dolphin is able to remain underwater indefinitely, survive the crushing pressures of the deep, and swim with a speed far outstripping that of the sleek undersea mammal for which she is named.
Above land, Dolphin has the slightly enhanced strength and eyesight of one who has lived her life underwater. Her enhanced strength and unnatural cunning make up for her lack of hand-to-hand combat experience.
Contributed by Jeff Harvey