Harry Potter and his cousin Dudley are attacked by Dementors as they leave the park. Harry casts a Patronus charm to save Dudley from the Dementors Kiss, an attack that steals one's soul. Order of the Phoenix members soon arrive to escort Harry to their secret headquarters at the Black family home, Number Twelve, Grimmauld Place in London. The Weasley family, Hermione Granger, and Harry’s godfather Sirius Black are there. Harry learns that Voldemort is building an army and is attempting to retrieve a "weapon". Meanwhile, the Ministry of Magic charges Harry with performing underage magic. A few days later, Arthur Weasley escorts Harry to his hearing where he is cleared after testimony from Albus Dumbledore and Harry's neighbour, Arabella Figg (who is a Squib).