Johnny Maxwell is a fictional character in a series of three children's books by Terry Pratchett. He is a young boy (twelve in the first book, but a teenager in the later ones) living in the (fictional) typical late-20th-century English town of Blackbury (also the setting of Pratchett's Truckers).
Johnny has a difficult home life. Over the course of the three books his parents split up and he and his mother move in with his grandfather. This may be why he starts seeing things no-one else sees, including an alien surrender party, ghosts and a time travelling bag lady. On the other hand, it is possible that he sees them because they are actually there and he lacks the filters that stop most people noticing how amazing the world is (a favourite theme of Pratchett's).
Apart from this tendency Johnny is almost unnaturally normal. His friend Kirsty often gets exasperated by his tendency to simply accept that strange things happen to him, rather than doing something about it. He has a strong sense of fair play, which leads to him fighting for what's right even when he has no idea what's going on.
The Gang 
Johnny has a sort of a gang consisting of the kids who hang around with each other because they don't fit into any of the school cliques. They are:
- Stephen 'Wobbler' Johnson. Johnny's best friend and the second main character in the book. He is overweight and heavily into computers, an expert at piracy. He wants to be a nerd, but they wouldn't let him join. It is his considered opinion that Johnny is mental. His real name is Stephen Johnson in the books, although the television adaptation of Johnny and the Bomb gives it as Walter. In Johnny and the Bomb Wobbler got stuck in 1941 and grew up to be a billionaire calling himself Sir John (Sir Walter in the TV version) but, due to the time travel and multiple timelines involved, where and if this happened is questionable. Certainly a Wobbler returned successfully from 1941.
- Simon 'Bigmac' Wrigley. An asthmatic skinhead who is deeply embarrassed by his instinctive grasp of mathematics. He lives with his brother in a rundown tower block on the edge of Blackbury. He is not exactly a criminal but has a confused grasp of car ownership.
- Yo-less. A West Indian boy so nicknamed by Johnny because he doesn't say "Yo!". Interested in Star Trek, train spotting, Morris dancing and brass band music. His reaction to those who are surprised a black kid has such "uncool" hobbies varies from amusement to irritation. When faced with genuine racism he has a brittle anger that manifests itself in cold, almost emotionlessly delivered, sarcasm.
- Kirsty. (Also known as Sigourney, Kimberly, Klytemnestra and Kasandra). Unlike the rest of the gang, Kirsty is a highly organised person who knows exactly where she's going in life. She is highly intelligent but has very poor people skills, something she views as a character flaw in everyone else. She is trying to get Johnny's life organised since he is clearly incapable of doing it himself, but hasn't realised that he doesn't especially want his life organised. He finds her very easy to talk to since she never listens. Unlike her most obvious Discworld counterparts, Susan Sto Helit and Granny Weatherwax, Kirsty has a tendency to romanticise things hidden beneath her practicality and finds Johnny's down-to-Earth attitude to things almost as annoying as his lack of direction.
Recurring characters 
- Mrs Tachyon
- Seargant Comely
- Arthur Maxwell
- jhonny Maxwell
The novels 
The Johnny Maxwell books are:
Other media 
"I just see things other people don't see" 
I can't be having with that pernicious rubbish ... To Johnny it's all real, and that's what counts ... He deals with all the problems on their own terms and half the time he's projecting reality onto fantasy.... So: is what happens in the books real? Yes. Does it all happen in Johnny's head? Yes.
- alt.fan.pratchett, 22 February 1997, .