Let me begin by saying I love the “City Spies” series by James Ponti, and his newest entry, “Forbidden City,” is no different. The story is gripping from the start as we read about Paris, one of the young spies, climbing the side of a mansion to return to the billionaire owner a priceless Fabergé egg which, unbeknownst to him, had been swapped for a exact copy containing a bug that allowed British Intelligence to spy on him. He is loaning the priceless treasure to a museum where the deception would surely be uncovered. Paris is named for the city where he was recruited. All the young spies are thusly named, Kat was recruited in Kathmandu, Sydney in that Australian city, Rio in Brazil, and Brooklyn in that New York borough. All live together in a manor home in Scotland with Mother and Monty, two MI6 agents. They attend an exclusive private school and work on spycraft in their spare time. And, in each novel, they have a mission.

In this book, we learn that the evil anarchist group Umbra—that the spies have foiled in the past—has stolen nuclear warheads and now is planning on kidnapping a North Korean nuclear scientist to help them create nuclear weapons. Because the mission takes the group from Scotland to Moscow to Beijing, we readers get to visit those locales vicariously. The billionaire who is involved with Umbra dotes on his teenage daughter, Tabitha. Sydney poses as a journalist and travels by private jet with his daughter, writing and posting videos of Tabitha’s clothes and activities for the teen outlet. Paris has a different role and must perfect his chess game to pose as a chess prodigy. The objective is for him to meet the scientist’s son at an international chess competition that the billionaire is sponsoring. The scientist is not allowed to leave North Korea, which is typical for repressive regimes, but when his son might win an award at an international chess tournament, thus making North Korea look good, they allow participation. There’s a clever nod to the first two books when, during the opening caper, there’s a photo booth at the posh party at the mansion and “guests could have their pictures taken in front of international backgrounds featuring landmarks like the Eiffel Tower or the Golden Gate Bridge.” The first two books feature those locations on their covers.

Ponti does a very creditable job in terms of character development. Sometimes, in a book with multiple main characters, that can be difficult. But he gives readers real insight into how Paris, Brooklyn, and Kat feel. I especially enjoyed reading the Ponti version of “How to Win Friends and Influence People” in his succinct explanation of the acronym KISS. Rio is trying to help Kat become a more charming, more approachable, friendlier person. Her strength is solving puzzles and math, but when it comes to figuring out people, she is completely lost. He explains that the K in KISS is for kindness, the I is interest, “You have to be interested in the other person and what they are interested in.” The two S’s represent sensitivity and sincerity. I’d love to discuss that concept with a group of 4th or 5th graders and see what they think of that idea.

Ponti’s genius is that he has created a middle grade series about child spies, and the books are filled with practically nonstop action, but he has also imbued the story with real emotion. Mother, the agent in charge of the group, adopts them and becomes their father, and Ponti makes it apparent how important is for kids to be a part of a family. We also learn the story about how his spy name became “Mother,” and it’s very touching. The kid spies themselves model integrity and determination. They must deal with intelligence leaks and foiled plans. While the group saves the day and this story has a happy ending, we know that Umbra still exists and will be attempting to perpetrate other acts of devastation and destruction in future books. And because Ponti has made us really care about these people, the kids but also Monty and Mother, we can’t wait to see what the future holds for them.

Note: if you haven’t already read the first book, “City Spies” or the second, “City Spies: Golden Gate,” you’ll want to read those first to add to your enjoyment of this one. While this book does work as a stand alone novel, your understanding of the characters and their development will be enhanced by starting at the beginning.

Please note: This review is based on the advance reader’s copy provided by Simon & Schuster, the publisher, for review purposes.