Summer of the Sea Serpent

The #1 bestselling chapter book series of all time invites young adventurers to dive into another thrilling quest with Jack and Annie! In this enchanting Merlin Mission, the beloved sibling duo embarks on a mystical journey through underwater caves, encounters a mysterious Spider Queen, and discovers the magic of selkies—all while searching for a legendary sword that could change everything.

This time, Jack and Annie aren’t alone. With the help of Teddy, a young sorcerer with tricks up his sleeve, they’ll navigate dangers both above and below the waves. Mary Pope Osborne weaves together fantasy, mythology, and heart-pounding adventure in a story that keeps pages turning faster than the tide.

Perfect for growing readers ready for more challenge. Part of the Merlin Missions series, this book offers a slightly more complex adventure than the original Magic Tree House stories—ideal for kids who’ve mastered early chapter books and are hungry for deeper plots and richer vocabulary. The accessible writing style and short chapters make it perfect for independent reading or sharing aloud on a rainy afternoon.

Whether your young reader is already a Magic Tree House fan or just discovering this beloved series, Summer of the Sea Serpent delivers the perfect blend of magic, mythology, and friendship. It’s the kind of book that sparks imagination and makes kids excited to read just one more chapter before bedtime.

Formerly numbered as Magic Tree House #31, now Magic Tree House Merlin Mission #3.

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