"Substitute Creature" is the second segment of the tenth episode of The Adventures of Jimmy Neutron: Boy Genius.
In his lab, Jimmy has finished cloning a 64,000,000-year-old piece of spinach stuck between a museum dinosaur's teeth. He shows off over him being a good genius to clone this magnificent specimen. He monitors his show-off ratio to keep Cindy from calling him a know-it-all. It overloads after he explains that it's hard to be a know-it-all when do actually know it all. Judy then calls Jimmy for breakfast. He misses out and rushes to school with his spinach in time for his botany project. For breakfast, Hugh gets toast, but not toasted. He complains of the toasters he's bought and how Jimmy always converts them into something else (window washer, newspaper deliver, face decorator).
At school, Sheen, for his botany project, brings a boxing glove glued to a fern which he describes as, "The rare Punching Plant of Melborn 9." Libby brings plants sensitive to musical stimuli. One got 2 hours of classic R&B, while the other got 2 hours of yodeling to the oldies (a dead plant).
At Jimmy's house, Hugh spots an ad for a toaster convention at the convention center. He begs Judy to go and says okay. Judy does her face with the face decorating toaster and looks like a clown.
Back at school, Cindy brings her plant. It is a large, pink, overwatered plant that the kids in the classroom seem to love besides Jimmy's piece of spinach who has just arrived. Jimmy digs through his locker for his DNA accelerator to make his spinach more impressing. During the botany project presentations, Ms. Fowl describes Cindy's flower during her presentation sweet and beautiful and Jimmy's spinach, who is sitting, smelly and unexciting (Cindy then sticks her tongue out at Jimmy). Then, Jimmy uses his accelerator to enhance the spinach's DNA by 350 million years. Jimmy's turn to present his spinach comes up. While he presents to the bored class, three surging purple seeds from the spinach (which bloomed) shoot into Ms. Fowl's mouth. She wakes up like a plant monster and grows so her head reaches the ceiling. This scares the class who run away. Cindy finds Carl and Sheen in the men's bathroom looking for Jimmy. Carl and Sheen don't know until Cindy leaves. Jimmy is hiding in a bathroom stall. Out of the bathroom, Ms. Fowl left a huge hole in the school. Jimmy calls Goddard for a screwdriver and his special CD of town-saving music.
In downtown Retroville, Ms. Fowl is over 100 feet tall and is crushing buildings and automobiles. She heads towards the convention center where the toaster convention is being held and takes off the ceiling which is shaped like 1/2 a basketball. At a military base, Ernest Abercrombie orders jets to be sent to Retroville to stop Ms. Fowl. Abercrombie is in one of them and gets caught by Ms. Fowl who says, "Is that you, Ernest Abercrombie? Where is your homework? It's 28 years overdue!"
Jimmy, Carl, and Sheen arrive at the scene, and Jimmy calls General Abercrombie to hold his fire in order to shrink Ms. Fowl. Goddard comes back with the CD and screwdriver. Jimmy's mom and dad scram from the scene and watch from the parking lot where the boys are. Hugh's holding a new toaster. Jimmy finds out the DNA accelerator's battery is low (low enough to not hit Ms. Fowl). So Jimmy jetpacks to Ms. Fowl (with the town-saving music on) with the accelerator and starts shooting at her, and the rays barely hit Ms. Fowl. Jimmy gets an idea of using Hugh's new toaster to "toast" the accelerator into Ms. Fowl's mouth. Hugh doesn't want to let go of the toaster, but Goddard retrieves it, and he sends it to Jimmy. Jimmy "toasts" the accelerator into Ms. Fowl's mouth and it finally works.
Ms. Fowl shrinks and loses all of her spinach. The crowd cheers for Jimmy and Cindy proves (while holding three seeds) that the seeds were responsible for the mess. Carl thinks the seeds are lunch and eats them accidentally. He grows large, and forms spinach. He doesn't get all ravenous like Ms. Fowl. Jimmy leaves while Sheen, Cindy, Libby and Nick confuse Jimmy's order to get the accelerator out of Ms. Fowl's stomach, but Sheen thinks that he needed to. Then the town-saving music appears, Sheen, Cindy, Nick and Libby leave while Carl dances to the music.
Home video releases
- The Adventures of Jimmy Neutron: Sea of Trouble
- The Adventures of Jimmy Neutron: The Best of Season 1