Batman (1966)

S2E60 The Duo Defy

In his icy lair, Mr. Freeze coerces the abducted Professor Isaacson into constructing a powerful thermodynamic ice ray. He threatens to freeze the entire nation unless his conditions are satisfied and showcases the destructive capability of his weapon. While the villain formulates his demands, Batman and Robin trace his seal, Isolde, through the frozen waters of Gotham Harbor to uncover the location of his hideout.