From Wikipedia

The Dragon's Lair is the third book in The Lost Journals of Ven Polypheme series by Elizabeth Haydon and published in June 2009. The book is illustrated by Jason Chan. Read more - Shopping-Enabled Wikipedia on Amazon

From School Library Journal

Grade 5–9—In this addition to the series, Ven and his friends go on a quest to escape the Thief Queen and stop a dragon from destroying Nain settlements. Amariel, a merrow (or mermaid) who once saved Ven's life, reluctantly agrees to join in the quest. This decision proves dangerous when Ven loses her cap and must race against time to find it before Amariel turns human forever. Though not a stand-alone, the book has a richly drawn fantasy world, distinct characterizations, and a fast pace that will inspire readers to check out The Floating Island (2006) and The Thief Queen's Daughter (2007, both Tor). Peppered with energetic sketches and excerpts from Ven's journals, this unique book will appeal to a broad range of readers.—Kim Ventrella, Ralph Ellison Library, Oklahoma City, OK
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