The Black Book of Buried Secrets is a bonus book in The 39 Clues series released on October 26, 2010. It was writen by Mallory Kass and contains an introduction by Rick Riordan.
The Black Book of Buried Secrets is a bonus book in The 39 Clues series released on October 26, 2010. It was writen by Mallory Kass and contains an introduction by Rick Riordan.