'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.Plot summaryAmy, Dan, and their au pair, Nellie Gomez, found music by Wolfgang Amadeus Mozart in the end of The Maze of Bones, leading them to Vienna, Austria, to learn about him and find a related clue. In Vienna, Amy and Dan discover that Mozart had an older sister: Maria Anna "Nannerl" Mozart. They go to a library to view her diary, only to realize Jonah Wizard, a fellow competitor in the search for The 39 Clues, stole it. They steal it from him, but then Nellie translates it and notices that three pages are missing.After finding the music from Mozart on the Internet, Amy and Dan notice that three lines are missing from it. They play the missing lines down in the lobby of the hotel they are staying in and realize that they are actually a whole different song that wasn't even written by Mozart. That song's name is "The Place Where I Was Born", so they go to the place where Mozart was born: Salzburg, Austria. There, they see Alistair Oh (yet another competitor), and follow him into the Salzburg Catacombs. They see the man in black (who is always around when bad things happen) and, shortly afterward, are trapped inside the Catacombs by an explosion that causes a cave-in. However, they find another way out through St. Peter's Archabbey and are chased by monks after finding a sheet of old parchment that supposedly had all 39 clues on it. They are devastated to find that it is just a recipe for Benedictine.