Вот здесь можно найти кратенькое описание основных персонажей поттерианы, а тут - не менее краткое содержание первых пяти книг. Все на аглицком.
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SEVERUS SNAPE: Head of Slytherin House, Snape is professor of potions. But he really wants to be the defense-against-the-dark-arts teacher. From the minute Harry arrives at Hogwarts, Snape detests him. But while he does many things to make Harry's life difficult, he's also something of a contradictory character. The first year, he kept Harry safe - an act of honor since James Potter once saved his life. A former Death-Eater, he left Voldemort's service and went to work for good. That makes Dumbledore trust him, even though others don't.
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