The 39 Clues Books in Order

The 39 Clues universe is a globe-trotting puzzle series built around the secretive Cahill family, whose branches have quietly steered world history for centuries. Riordan launched the franchise with The Maze of Bones, which introduces siblings Amy and Dan Cahill and the idea of thirty-nine hidden ingredients to a powerful serum. Later, he returned to the world for Vespers Rising and the companion The Black Book of Buried Secrets, helping to define the big mysteries that drive the early arcs.

In the core stories, Amy and Dan are offered a choice at their grandmother’s funeral: walk away with a comfortable inheritance or join a high-stakes hunt for the clues. They pick the dangerous option and find themselves racing rival branches through catacombs, castles, libraries, and labs, piecing together riddles tied to figures like Benjamin Franklin, Napoleon, and Mozart. The tone is quick and quippy, with very short chapters and constant cliff-hangers.

Every book feels like a mix of spy story, travelogue, and family drama.

Because The 39 Clues is a multi-author project, Riordan’s titles sit alongside novels by other writers, plus card packs and online games. On this page we focus on the books he wrote or co-wrote and explain how they thread into the larger storyline. The Maze of Bones kicks everything off. Vespers Rising bridges from the original clue hunt into the Cahills vs. Vespers sequence, while The Black Book of Buried Secrets functions as an in-world dossier that deepens the backstory behind key characters and branches.

If you’re reading just for Riordan, you can treat his titles as a self-contained mini-arc that sketches the stakes and mythology of the Cahill family. If you plan to dive into the full series, this page will help you slot his books into the broader reading order so you see major reveals in the intended sequence.