"The Cat's Meow"
Catwoman feigns surrender and gasses the caped crimefighters. She then locks them in a two-tonne echo chamber that magnifies every sound ten million times. Water is being dripped onto the roof, producing drum-like vibrations that send Batman and Robin into agony. She intends for their eardrums to shatter and their brains to turn to "yeuch", so that Batman will become her mindless slave.
Batman realizes that the room's sympathetic vibration is F sharp above high C. He and Robin then hum that note until the glass explodes, freeing them.
Catwoman steals the voices of a British boy band!