In a world filled with mad scientists and evil inventions, one talented evil scientist's hunch-backed lab assistant has big dreams of becoming a mad scientist himself. He dreams of winning the annual evil science fair. Determined to prove he can create his own diabolical invention, Igor creates a female Franken-monster. But his creation, Eva, is sweet and sings. That is, until she falls into the clutches of Dr. Schadenfreude.

Quasimodo ventures from his tower to the joyous festival of fools, but the crowd turns cruel and rejects him because of the way he looks. The gypsy Esmeralda rescues him and he finds himself battling to save the people and the city he loves--while reminding us to see people as they are rather than how they appear.