Kindly Dr. Lazlo Jekyll, with his assistant Dr. Jonathan Marvel, is trying to discover a potion to bring out the best in mankind. What he discovers instead is the mean and wicked Mr. Hyde within himself. Fiendish Mr. Hyde proceeds to go on a rampage of cruel and wicked behavior with the help of his housekeeper and former music hall dancing girl, Muriel Snipe. Will the sweet and innocent Ivy Goodall be caught in the evil web of Mr. Hyde's cruelty? Can Ivy's blustery uncle, Brigadier Hugh Huffin-Puffington, and fearless Dr. Marvel save her from Hyde's revolting clutches?