Fatjohn, Frederick, & James is the first installment of Fatjohn Adventures. Below are profiles of characters, both major and minor, from this installment.
- Fatjohn Orange - the main character of this installment. He shows that he is annoyed by James's behavior. Fatjohn is voiced by John Brimm.
- Frederick Kalgarron (voiced by Curtis Kilprus) - one of Fatjohn's passengers. He is originally supposed to drive his own truck, but his truck has problems while being loaded in Yatesburgh, Arubio. His voice is similar to Austin Blizz from the following installment, but Kilprus does not voice Austin. Austin is voiced by Austin Samalee.
- James Laww (voiced by Bob Kolbern) - one of Fatjohn's passengers. He, like Fatjohn, is from America. He is known for using bad grammar ("I ain't heedin' nothin'", "We is perfect! Frederick's brother is the one who ain't perfect", "Now, I ain't from no Planet Stupid"), rude belching, and heavy drinking and smoking. His voice and mannerisms are based on those of Frank Patrick from the TV show Frank & Amos. It is learned in the installment that he is superstitious (unlike Frank).
- Jarita Alin (voiced by Annie Hadskins) - a nice, recently-widowed woman in her late thirties whom Fatjohn meets in Arondello, Lohana. She falls in love with Fatjohn, and they end up marrying sometime after this installment, as Fatjohn had divorced his wife years before this installment takes place. Jarita shares Fatjohn's intolerance for James's behavior.
- Jaycroff Swindell (voiced by Scott Buchanan Gelch) - a trucker whom Fatjohn and his crew meet in Carlana, toward the end of the installment. Jaycroff likes "shooting the breeze" (talking) with people, and it is learned that he does not read directions, nutrition facts, ingredients lists, or other helpful labels carefully.
- Benjamin "Ben" Orange (voiced by Scott Buchanan Gelch) - Fatjohn's brother. It is learned that he watches over Fatjohn's two sons while he is on the road. He is known for starting sentences in a nice voice and then yelling before the end of the sentence, usually with the yelled part serving as a command to someone other than the person he is talking to when he starts the sentence ("I'm about to tell them to put the candy up!"). *The part in bold is the command.*
- Phenyx (voiced by Scott Buchanan Gelch) - Phenyx is one of a group of people who interrupt Fatjohn and his crew's trip in order to defeat them and steal their vehicle. Phenyx and the gang's plan backfires, as Fatjohn and his crew come out victorious. He talks so fast that hardly anyone understands what he says.
- Bryan Oxnard (voiced by Bob Kolbern) - an employee at a truck stop in west-central Lohana. He likes to keep order in the store, and cannot be coaxed into breaking laws, as is proven when he says, "We sell no alcohol to drivers."
- Ol' Birch (voiced by Jordson Hayes) - "Ol' Birch" is the CB handle of Harry McGandleberg. He is a trucker who talks on the CB radio briefly with Fatjohn, telling him about how things are going downhill for him in Elnard, Abercame and how he has a load bound for Longstown, Salviana by Friday of that week. He was thought to have been in prison by Fatjohn because of rumors.
- Oskar Engfell (voiced by Scott Buchanan Gelch) - Oskar (not "Oscar") is a customer at the truck stop where Bryan Oxnard works. He gets into a quarrel with James, and the quarrel is broken up by Bryan, who obviously does not condone violence or word battles.
- "Scrumptious Pizza" man (voiced by Bob Kolbern) - This unnamed man appears in the beginning, when Fatjohn and his crew stop at a truck stop in Fellertown, Arubio. He only says two sentences ("That was some scrumptious pizza. You can keep the change.") Those sentences, of course, follow a big belch.
- Jhoe (voiced by Jordson Hayes) - Jhoe is a minor character who appears toward the beginning. He shows up inside the Fellertown truck stop without any shoes, thus violating the place's dress code policy. Bob the employee is quick to remind him of the policy.
- Gus the Boss (voiced by Bob Kolbern) - Gus is the leader of the group which Phenyx is a part of. He has zero tolerance for disobedience, and shows this by punishing his own workers harshly. According to Fatjohn, he has no friends because of his ruthlessness.