An unnamed alley cat searches for food in some garbage cans late at night. Unable to find anything worth his while, he spots a refrigerator inside a house and heads for it. He sneaks onto the property only to wake a sleeping bulldog. The bulldog chases the cat up to the side of the house. The cat quickly pulls out some sleeping pills, putting the dog into a deep sleep. Once inside, the cat searches for food in the kitchen, but comes up empty. His luck finally changes when he notices a can of cat food. He quickly opens the can and out pops a mouse, who is plopped down onto a dinner plate. The cat is about to dig in with a fork, but the mouse puts a quick stop to that. He says that the cat can't eat him because he has already seen the cartoon they are in, and that he winds up saving the cat's life later. The feline understands, but wants some food as he is starving. The mouse points into the other room and tells him that there is a huge, fat, tasty canary in there. The cat charges out into the other room and stuffs the unseen canary into a sack heading back to the kitchen. The bird is emptied from the sack, to be revealed as scrawny and little. The bird tells the cat, "Well, I've been sick...". Disgusted with the tiny creature at first but still desperate, the cat gets a brainstorm when he sees a bottle of Jumbo-Gro plant growth formulaon the shelf. Quickly, he pours some of the formula into the bird and sure enough, the canary grows rapidly in size. But before the cat can take a bite, the bird is already over 10 feet tall. The canary takes advantage of his new height and beats up on the cat. The cat turns the tables on the bird and drinks the Jumbo-Gro formula himself, doubling in size until he is much bigger than the bird. He tosses the potion out of the window only for it to land in the bulldog's mouth. While the now giant-sized cat chases the slightly smaller canary through the side of the house, the bulldog guzzles down the formula. After a quick run around the block, the cat and canary wind up back outside of the house, where a now gigantic bulldog appears before them. The cat runs away in fear as the bulldog tosses the bottle of plant growth food down the chimney, where it rolls out of the fireplace and straight to the mouse inside the living room. The dog leaps over the house and chases the cat into the city. Meanwhile, the mouse takes a few sips of plant food, instantly ballooning to gigantic size. The dog chases the cat to the city, only for the now gargantuan mouse to show up and scare the bulldog away with a simple "Boo!". The mouse who is as tall as a 20-story building and just as fat, reminds the cat that he told him he would save his life. The cat thanks him as the mouse hands him the bottle back and waddles off. The cat, rubs his enormous belly realizing he still is hungry, sees the huge mouse stomping off and gets another idea. He suddenly drinks more of the formula and grows even bigger and fatter than the mouse. The cat who is by now 100 stories tall, chases the giant but smaller mouse through the city and across the country, passing the Grand Canyon, Hoover Dam, and the Rocky Mountains. The giant mouse hides in a railroad tunnel, losing the cat for a moment. The mouse drinks the potion when the cat isn't paying attention and becomes even bigger than the already huge cat. The mouse starts to beat up on the cat only for the cat to take the potion back and drink it, becoming bigger than the mouse. The mouse takes it back and drinks more to become bigger still. They continue getting bigger and bigger, fatter and fatter until they suddenly both come to a stop at the same exact size. They shake the now empty bottle of Jumbo-Gro and tell the audienceat home that they have to end the cartoon, as they've run out of the formula. They wave goodbye to the audience before the camera pulls back, revealing that they have outgrown the Earth itself and are standing atop the globe.
The Simpsons episode "Itchy and Scratchy and Marge" reproduces the climax, with Itchy and Scratchy shooting each other with ever-larger handguns. "Planet of the Capes", an episode of Darkwing Duck, has the hero and villain repeat the final sequence with an energy gun that makes them grow. At the end, the villain rebuilds his gun to work in reverse. However, Darkwing Duck shoots himself with it, leaving the villain to stand on the planet alone. An episode of Dexter's Laboratory titled "Monstory" parodies the short, in which Dexter and DeeDee repeatedly drink a formula that transforms them into increasingly giant monsters. Like the Avery short, the episode ends with both Dexter and DeeDee on top of the globe.
