What number book in the Harry Potter series involves Snape becoming a double agent on behalf of Albus Dumbledore?
Severus Snape Severus Snape is a fictional character in J. K. Rowling's "Harry Potter" series. An exceptionally skilful wizard, his coldly sarcastic and controlled exterior conceals deep emotions and anguish. A Professor at Hogwarts School of Witchcraft and Wizardry, Snape is hostile to the series' protagonist, Harry, the moment he sets foot in Snape's classroom; this hostility is rooted in Harry's resemblance to Harry's father James, who bullied and harassed Snape during their time at Hogwarts. Though philosophically attracted to the Dark Arts and Lord Voldemort's ideology of wizard supremacy, Snape's love for Muggle-born Lily Evans, Harry's mother, eventually compels him to defect from the Death Eaters. Snape becomes a double-agent on behalf of Albus Dumbledore and the Order of the Phoenix, and protects Harry throughout the series.
Spy Hook Spy Hook is a 1988 spy novel by Len Deighton. It is the first novel in the second of three trilogies about Bernard Samson, a middle-aged and somewhat jaded intelligence officer working for the British Secret Intelligence Service (MI6). "Spy Hook" is part of the "Hook, Line and Sinker" trilogy, being succeeded by "Spy Line" and "Spy Sinker". This trilogy is preceded by the "Game, Set and Match" trilogy and followed by the final "Faith, Hope and Charity" trilogy. Deighton's novel "Winter" (1987) is a prequel to the nine novels, covering the years 1900-1945 and providing the backstory to some of the characters.