James "Jimmy" Isaac Neutron is the main protagonist of the Jimmy Neutron franchise.
Jimmy is a boy with a stunning IQ and a love for science. From Hypercubes to Hypnorays, Jimmy can whip up the most amazing inventions. However, things have a way of going awry, and more often than not, Jimmy has to save the day from himself.
In the XP4 fics, Jimmy is currently working at the Heroes Coalitions as part of the Science and Research Department. He also attends Vanguard Academy as a student.
Jimmy is a young boy with a big forehead, blue eyes and a large brown cowlick, ice cream sundae hairstyle. He wears a labcoat over a red shirt, blue pants and red & white sneakers.
Jimmy has an impossible I.Q. of 210, making him the smartest Retroville citizen and quite possibly the smartest individual in the whole world. He specializes in many sciences such as quantum physics, chemistry, biology, mathematics, robotics, engineering and astronomy. In a number of episodes, his classmates are annoyed and angered because Jimmy's brilliance renders trying to win science projects and competitions things pointless. In fact, Jimmy has been banned from the science fair for life to give normal kids an actual chance. His brain, a source of constant comment, allows him to invent devices that accomplish even the impossible. That might seem like a gift to most people, but to Jimmy, it often causes him trouble.
- In the episode "Grumpy Young Men", he has a head similar to Albert Einstein.
- Jimmy's original name was Johnny Quasar and didn't have his large brown cowlick. They changed his name because it sounded too much like "Jonny Quest".
- In the shorts, pilot and the movie, Jimmy's voice was more scratchy, nasally and high-pitched. In the series, his voice became more deep and clear.
- During the time of the movie and the early years of the show, Jimmy became Nickelodeon's official mascot.
- Jimmy, Carl and Sheen are the only characters to be in every episode of the series.
- In Planet Sheen, Jimmy is mentioned in the pilot when Sheen questions the J.N initials on the notes.
- There was going to be a TV movie about Jimmy and the others going to Zeenu to find Sheen, but due to low ratings, production costs and several writers moving on, the movie was cancelled.
- Jimmy is ten in the shorts and movie, eleven in the first season, and twelve for the rest of the series.
- Jimmy and Nick are the only male characters to be voiced by a female. Jimmy is voiced by Debi Derryberryand Nick is voiced by Candi Milo.
- However, in the dubs such as Spanish, he is voiced by boys rather than women or men. Eduardo Curiel voiced Jimmy in the Latin American dub of the movie, and in the first season. His voice is noticeably different in the TV show due to reaching puberty where he can no longer sound like a kid. So he is replaced by a younger actor, Diego Ángeles. Some viewers agreed that Eduardo Curiel gave Jimmy the best voice.
- Other voice actors who auditioned to voice Jimmy included Nancy Cartwright, E.G Daily and Pamela Adlon.
- Throughout the show, it is constantly hinted at that Jimmy inherited his intelligence from his mother, who has shown certain degrees of brilliance herself like when in "See Jimmy Run", she explains how the overwhelming speed of the shoes could cause his shoes to meltdown. In fact, in the book Genius 101, he even comments on Judy's cleverness and Hugh's bumbling nature, saying that is quite obvious where he got his intellect. However, in "Clash of the Cousins", Jimmy analyzed the "Neutron genius gene" which actually comes from his father's side of the family. Although, it is a possibility that both sides of the family carry an individual genius gene.
- In the pilot Runaway Rocketboy, Jimmy wears a striped shirt instead of his trademark atom shirt. A photo of him in this shirt can be seen on the staircase often in the show.
- It would appear that Jimmy has Autism, which is quite common in science geeks.
- Sometimes, Jimmy speaks redundantly.