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The 39 Clues: The Cahill Files Books in Order | Wonderlit

The 39 Clues: The Cahill Files

1 books · Ages 8–12

The 39 Clues: The Cahill Files is a 1-book series for ages 8–12 by Clifford Riley.

Where to Start

Operation Trinity

Start at the beginning: Operation Trinity

This is a sequential series — each book builds on the last. Start with book 1.

Reading Order

Operation Trinity

Operation Trinity2012

Also in this world

Spymasters

What This Series Covers

Teamwork & Collaboration Good vs. Evil Resilience & Perseverance Love & Family Fear & Bravery Puzzles & Games

All books by Clifford Riley →

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