Since his last encounter with Batman, Mr. Freeze has found a home in the Arctic and started a family (of sorts) with the still cryogenically encased Nora, an Inuit boy named Koonak, and two pet polar bears, Notchka and Chokka. A nuclear submarine, unaware of the presence of Freeze and his companions in an ice cave, surfaces on an arctic exploration and shatters the cave, breaking Nora's encasement and leaving her life in danger. The distraught Freeze returns to Gotham City with his companions, and enlists the help of Dr. Gregory Belson to find a cure for Nora. Belson determines that Nora needs an organ transplant, but due to her rare blood type, there are few suitable donors available. Unfortunately, one of these few donors listed is Barbara Gordon, and she is kidnapped to a mid-ocean drilling rig for the operation. It's up to Batman and Robin to rescue Barbara before it's too late.