Hare Remover.Mad scientist Elmer tries his best to make a "Jekyll and Hyde potion", but his experiments always end in failure, causing one of his test animals, a dog, to run out and eat grass. He decides to trap a rabbit (Bugs Bunny) as his next subject. After he traps him, Elmer gives Bugs the potion, but to no avail. Elmer has a crying fit until Bugs gives him one of the potions, giving Elmer the same initial looney side effects the other animals had experienced. When a bear enters the lab from the nearby forest, both Bugs and Elmer mistake the bear for one another, until Elmer becomes angry at the bear (still thinking that it is Bugs) after the bear refuses the potion that was going to cure him, which was the same potion Bugs gave to the bear earlier and of which made the bear disgusted. Elmer scolds the bear until he discovers that the bear isn't Bugs Bunny when the real Bugs is at the window. Elmer realizes his mistake, and the enraged bear chases Elmer and ends up on the warpath against him, while Elmer is sobbingly panickedly begging the bear not to literally kill him. Elmer, after heeding Bugs' option, plays dead to fool the bear, and is saved by his bad odor . Elmer thinks he's safe until he thinks he hears the bear again.. Meanwhile, the bear is standing on the side of the room watching them, convinced that both Elmer and Bugs are crazy, flashing rebus picture cards to the audience showing a screw with a ball, a cracked pot, a dripping faucet, bats in the belfry, etc.