 Bugs Bunny obliges Elmer Fudd by stepping into his crude rabbit trap and letting Elmer take him to his laboratory. That was a mistake. Elmer is a mad scientist trying to create a formula that will turn a "normal character into a devilish fiend." He pours a test tube full of liquid down Bugs s throat, but after a tableaux of agonized poses, nothing happens. Elmer is disconsolate, so Bugs cheers him up by having him drink some of the formula himself. Circumstances trick both Elmer and Bugs into thinking the evil mixture has changed the other into a bear. But the bear is a real bear, and the two antagonists had better watch out.