One False Note
One False Note is the second book in "The 39 Clues" series. It is written by Gordan Korman, and was published by Scholastic on December 2, 2008. Following the events of "The Maze of Bones", the protagonists Amy and Dan Cahill learn about Mozart and travel to Vienna, Austria to search for the second clue in the 39 Clues competition. "One False Note" entered the Children's Books New York Times Best Seller list at number one on December 21, 2008 and stayed on the list for children's chapter books for 12 weeks.
The 39 Clues
A pair of tungsten swords from Vienna leads Amy, Dan, and Nellie to Japan for a clue related to Japanese warrior Toyotomi Hideyoshi. Teaming up with Alistair Oh and the Kabras, the three follow a trail of clues to Korea, where they stay at Alistair's house. The Kabras have an interesting coin. A book in Alistair's secret library leads them to a mountain called Pukhansan. The group finds an entrance to a cave that uses the coin and hides Hideyoshi's treasure, and the third clue, gold. Dan decodes an anagram and tricks the Kabras, who escape and seal everyone else in the cave. Alistair is presumed to be dead but faked. After escaping, Dan, Amy, and Nellie head for Egypt, as hinted in the anagram.