Night of the ninth dragon - Mary Pope Osborne

The #1
bestselling chapter book series of all time celebrates 25 years with new
covers and a new, easy-to-use numbering system!

Please come to Camelot.
The magic tree house whisks Jack and Annie through space and time to
find that the castle of Camelot has been attacked and King Arthur has been
gravely wounded. To save the kingdom-and the king-Jack and Annie have
only one day to solve a riddle that will help them find a missing
dragon!

Formerly numbered as Magic Tree House #55, the title of this book is now
Magic Tree House Merlin Mission #27: Night of the Ninth Dragon.

Did you know that there's a Magic Tree House book for every kid?

Magic Tree House: Adventures with Jack and Annie, perfect for readers who
are just beginning chapter books
Merlin Missions: More challenging adventures for
the experienced reader
Super Edition: A longer and more dangerous adventure
Fact Trackers: Nonfiction companions to your favorite Magic Tree House
adventures

Have more fun with Jack and Annie at MagicTreeHouse.com!