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.
List of The 39 Clues characters
Grace Cahill (from Attleboro, Massachusetts) was the matriarch of the Cahill family. She died when she was seventy-nine years old. She had a jade necklace that she always wore until her death. She was a professional pilot, and had a private airplane that she flew around the world with, which she named "The Flying Lemur". During her life, she had been lonely due to the deaths of her relatives (her ex-husband Nathaniel Hartford, her daughter Hope Cahill, and her son-in-law Arthur Trent). Even though, she managed to keep all the Clues safe in her hands until her death just after she altered her will and thus started the quest. Her official cards are No. 59, No. 133, and No. 197.