During the Spring and early Summer of 1966 Gotham City witnessed several daring robberies committed by a ruthless individual described by witnesses as a glamorous-looking blonde in a black wetsuit. Her specific attire was due to a modus operandi which generally involved striking from and vanishing back into the ocean depths; which - combined with a capacity for violence that made that made Catwoman look like a girl scout - earned this evil mystery woman the code name 'Sea Hag' from the Gotham City Police.
In addition to killing several security guards, during her brief reign as Gotham City's Public Enemy #1 Sea Hag may also have committed two professional hits. The first was a shady millionaire businessman shot with a silencer in a suite overlooking the ocean on his guarded island mansion. The safe was also opened, but what was taken was never established and whether his death was simply because he was there, was a targeted hit that Sea Hag had been commissioned to carry out, or was killed for reasons of her own was never clear. Those guards that weren't themselves shot saw a blonde woman dive from the window of their erstwhile employer's suite, where they found his body and a hysterical young woman. When she eventually calmed down she confirmed their description that the assailant had been a slim blonde in a black wetsuit. As with the murdered businessman a blonde in a black wetsuit was seen in the water a few weeks later at about the same time a Gotham heiress drowned while swimming near her yacht in what could either have been a commissioned kill or an attempting kidnapping.
A raid on a chemical plant led Batman to deduce that she was planning to use the materials that she had stolen to poison Gotham City's water supply; possibly for the purpose of simple extortion or as an act of terrorism on behalf of foreign paymasters. The Caped Crusader thus intercepted the villainess on her way to carry out this atrocity. Never previously having shrunk from lethal violence during her earlier capers, Sea Hag true to form immediately responded by discharging a speargun at Batman, and when she missed pulled a knife with which she lunged at him. Batman's lightning-fast reflexes once again saved his life as her grasped her slender wrist and after a furious struggle managed to wrest the weapon from her gloved hand. While grappling with the Caped Crusader, Sea Hag badly scraped her shoulder against a rock. Her bleeding attracted two sharks, one of which snatched her by the shoulder in its teeth and dragged the struggling woman down into the depths before Batman could intervene.
The Caped Crusader still possesses the knife he managed to force from Sea Hag's grasp; and a black flipper that may have one of hers later washed up on Gotham Beach. But apart from that no trace of her was ever found; leaving two mysteries in her wake. Was Sea Hag torn to pieces by the sharks or did she somehow escape?
And just who was she?