Batman searches for diamond thief Mr. Freeze.

Firefly and Mr. Freeze team up to put their devastating plan into action: permanently putting Gotham City in a never-ending winter. Once the policeman's gala charity ball is put on ice, it's all up to the Batman.

The Penguin, Mr. Freeze, and Alfred's old school chum are all on the trail of a sunken treasure in Gotham Harbor.