Harry Potter and the Chamber of Secrets seven books had been published, Graeme Davis regarded "Harry Potter and the Chamber of Secrets" as the weakest of the series, and agreed that the plot structure is much the same as in "Harry Potter and the Philosopher's Stone". He described Fawkes's appearance to arm Harry and then to heal him as a "deus ex machina": he said that the book does not explain how Fawkes knew where to find Harry; and Fawkes's timing had to be very precise, as arriving earlier would probably have prevented the battle with the basilisk, while arriving later would have been fatal to Harry
Harry Potter and the Philosopher's Stone Potter and the Order of the Phoenix" is the longest book in the series at 766 pages in the UK version and 870 pages in the US version. It was published worldwide in English on June 21, 2003. "Harry Potter and the Half-Blood Prince" was published on July 16, 2005 and sold 11 million copies in the first 24 hours of its worldwide release. The seventh and final novel, "Harry Potter and the Deathly Hallows", was published on July 21, 2007. The book sold 11 million copies within 24 hours of its release: 2.7 million copies in the UK and