Harry Potter and the Chamber of Secrets, by J.K. Rowling, is the sequel to Harry Potter and the Philosopher's Stone. It is the second book in a series of seven Harry Potter books. The book was published on 2 July 1998. A film was theatrically released in November 2002.

Harry Potter and the Prisoner of Azkaban is the third book in the Harry Potter series of books by J. K. Rowling. The book was published on July 8, 1999. A film based on the book was released on May 31st, 2004, in the United Kingdom (released early due to popular demand) and June 4th in the United States and many other countries. To this day the book continues to be highly popular. This is the only Harry Potter book so far in which Lord Voldemort has not appeared in any form.