When unemployed web designer Clay Jannon applies for a job as night clerk in Mr. Penumbra's 24-Hour Bookstore, he finds a narrow, three-story shop where haphazardly arranged books must be accessed by ladders. Only an occasional customer visits, arousing Clay's curiosity. Helped by his techie friends, Clay uncovers a mysterious cult that is dedicated to solving a puzzle hundreds of years old. Ari Fliakos's narration convincingly captures the enthusiasm of the youthful narrator as well as the older Mr. Penumbra. An entertaining blend of old and new technologies, books vs. computers. Sloan's story, with its many references to a dragon trilogy, will appeal chiefly to young adults and those who read more for quirky plot than for character development. VERDICT Recommended for those seeking a light mystery that celebrates the digital age. ["Though the depiction of Google as a utopian meritocracy seems rather farcical, Sloan has created an arch tale knitting the analog past with the digital future that is compelling and readable," read the review of the New York Times best-selling Farrar hc, LJ 9/1/12.--Ed.]--Nancy R. Ives, SUNY Geneseo[Page 43]. (c) Copyright 2013. Library Journals LLC, a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.