what is the 'order of the phoenix'?
It is a secret organisation founded by Albus Dumbledore.
Harry Potter and the Order of the Phoenix (film)
. The building also serves as the headquarters of the Order of the Phoenix, a secret organisation founded by Albus Dumbledore which informs Harry that the Ministry of Magic is refusing to believe Lord Voldemort's return. 
harry potter cast in order of the phoenix Daniel Radcliffe , Rupert Grint, Emma Watson and others. when was the film 'harry potter and the order of the phoenix' released? 11 July 2007 in North America and 12 July 2007 in the United Kingdom. what are the names of some of the characters? Harry Potter, Ron Weasley , Hermione Granger and others. who is the director? David Yates.
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Harry Potter and the Order of the Phoenix (film) [SEP] Plot
During another summer with his Aunt Petunia and Uncle Vernon, Harry Potter is expelled from Hogwarts after he uses magic to save himself and Dudley Dursley from Dementors. Harry is whisked off by a group of wizards including Mad-Eye Moody, Remus Lupin and several new faces including Nymphadora Tonks and Kingsley Shacklebolt to Number 12, Grimmauld Place, the home of his godfather Sirius Black. The building also serves as the headquarters of the Order of the Phoenix, a secret organisation founded by Albus Dumbledore which informs Harry that the Ministry of Magic is refusing to believe Lord Voldemort's return. At the Order's headquarters, Sirius mentions that Voldemort is after a special object he did not have during his previous attack.