at the start of December 2006. Filming was put on a two-month hiatus starting in May 2006 so Radcliffe could sit his AS Levels and Watson could sit her GCSE exams. Live-action filming took place in England and Scotland for exterior locations and at Leavesden Film Studios for interior locations. Harry Potter and the Order of the Phoenix had its world premiere on 28 June 2007 in Tokyo, Japan, and a UK premiere on 3 July 2007 at the Odeon Leicester Square in London. The film was released in the United Kingdom on 12 July, and the United States on 11 July. Harry Potter and the Half-Blood Prince (2009) Voldemort and his Death Eaters are increasing their terror upon the Wizarding and Muggle worlds. Needing him for an important reason, Headmaster Dumbledore persuades his old friend Horace Slughorn to return to his prior post at Hogwarts. During Slughorn's Potions class, Harry takes possession of a strangely annotated school textbook, previously owned by the "Half-Blood Prince". In July 2007, it was announced that Yates would return as director. Kloves returned to write the screenplay after skipping out of the fifth film, with Heyman and David Barron back as producers. Watson considered not returning for the film, but eventually signed on after Warner Bros. moved the production schedule to accommodate her exam dates. Principal photography began on 24 September 2007, and concluded on 17 May 2008. Though Radcliffe, Gambon and Jim Broadbent (Slughorn) started shooting in late September 2007, other cast members started much later: Watson did not begin until December 2007, Alan Rickman (Severus Snape) until January 2008, and Bonham Carter until February 2008. Harry Potter and the Half-Blood Prince had its world premiere on 6 July 2009 in Tokyo, Japan, and was released in the United Kingdom and the United States on 15 July. Harry Potter and the Deathly Hallows – Part 1 (2010) Harry, Ron, and Hermione leave Hogwarts behind and set out to find and destroy Lord Voldemort's secret to immortality – the Horcruxes. The trio undergo a long journey with many obstacles in their path including Death Eaters, Snatchers, the mysterious Deathly Hallows, and Harry's connection with the Dark Lord's mind becoming ever stronger. Originally scheduled for a single theatrical release, on 13 March 2008, Warner Bros. announced that the film adaptation of Deathly Hallows would be split into two parts to do justice to the book