London Calling
In this sixth installment in the New York Times bestselling series from Edgar Award winner James Ponti, the young group of spies stage a rescue in Rome in another international adventure perfect for fans of Spy School and Charlie Thorne.
Cairo, the newest member of the City Spies, takes the lead when his sister disappears in Istanbul. Determined to save the family of one of their own, the team risks discovery as their search leads them to Rome. Meanwhile, there’s been intel that seems to threaten the royal wedding about to take place in Westminster, bringing the team back to the UK on an official case for MI6. With so much security all over the city, it’s harder than ever for the City Spies to go unnoticed. Will their skills be up to the task?
James Ponti
James Ponti writes the kind of books that make young readers feel like they’re in on the secret—that the world is full of puzzles, hidden missions, and brilliant kids just waiting to take the lead. With his knack for weaving mystery, humor, and heart into every chapter, Ponti has carved out a special space in middle-grade fiction—one where intelligence is celebrated and friendship is just as powerful as bravery.
Long before he was writing about young spies and sleuths, Ponti was crafting stories behind the scenes of TV shows. A former screenwriter and producer, he developed his storytelling instincts in the world of children’s television, learning the rhythm of a good joke, the importance of pacing, and how to keep a young audience hooked. That training grounds his novels in a cinematic energy—quick-witted dialogue, cliffhangers in just the right places, and characters that feel like real kids, not just plot devices.
City Spies
There’s something thrilling about watching a team come together—not just any team, but one made up of kids from around the world, each with a secret past and a very particular set of skills. City Spies taps into that energy with precision, turning the idea of elite espionage on its head and handing the mission over to the most unlikely agents: teenagers.
City Spies consists of six books and series is set to expand with the upcoming release of one more book. The current recommended reading order for the series is provided below.

