J. J. Arcanjo is a British-Portuguese author best known for Crookhaven, a children's adventure series built around an irresistible contradiction: a secret school where young thieves learn to break the rules so they can eventually put the world to rights. He fills that premise with elaborate heists, hidden passages, criminal skills, mysteries, and friendships, but beneath the fun is a persistent question about the difference between doing something illegal and doing something wrong.
Arcanjo grew up between the Algarve in Portugal and Devon in England. Books became especially important when he moved to the UK as a child and learned English through reading, an experience that helped shape his attachment to stories from an early age. He later studied Criminology and Psychology at Aberystwyth University before completing a master's degree in Creative Writing and Publishing at City University in London. He also worked in publishing before establishing himself as a children's author.
His background in criminology found an imaginative home in Crookhaven: The School for Thieves. The novel introduces Gabriel Avery, a gifted young pickpocket who expects trouble when he is finally caught stealing. Instead, he receives an invitation to Crookhaven, where students study subjects such as lock-picking, forgery, deception, and "crim-nastics." The school's philosophy turns the conventional idea of a criminal academy upside down: its pupils are taught how to become exceptional crooks so they can use those abilities against people who deserve to be stopped.
Published in 2023, The School for Thieves was shortlisted for the Waterstones Children's Book Prize and launched a five-book series following Gabriel and his friends through their years at Crookhaven. As their skills develop, the mysteries surrounding Gabriel's family and the criminal organization known as the Nameless deepen, allowing the books to grow from mischievous school adventures into increasingly ambitious heists with consequences beyond the school grounds.
Friendship and chosen family remain as important to the series as breaking into impossible places. Arcanjo's young thieves succeed through different talents and personalities, while the distinction between good people and bad people is rarely as simple as who follows the rules. The result combines the pleasures of a boarding-school story with mystery, crime fiction, puzzles, and high-stakes adventure.
The world of Crookhaven reached an even wider audience when the books were adapted into a BBC television series. For a story that began with a hungry boy picking pockets, it was a fitting expansion: Gabriel's secret school for thieves had escaped beyond the page.
Across his fiction, Arcanjo shows a particular affection for clever outsiders, elaborate schemes, and characters who discover that finding the right people to trust can matter more than following the rules.
