Professor Snape:
Severus Snape is the Potions master and Head of Slytherin house at Hogwarts. He has sallow skin, greasy hair, a hooked nose, black eyes and a severe dislike of Harry Potter.

Discovered in chapter 8
The Potions Master
During the start-of-term feast, Percy tells Harry that Professor Snape knows an awful lot about Dark magic, and that it’s widely known that Professor Snape would rather teach Defence Against the Dark Arts than his own subject.

Professor Snape’s dislike for Harry becomes obvious during the first Potions lesson of the year, in which he singles Harry out, firing questions at him; he sneers when Harry doesn’t know the answers and takes points from Gryffindor for Harry’s cheeky retort.


Discovered in chapter 11
Quidditch
After Hallowe’en, Professor Snape is seen limping and, later, nursing a wound given to him by the three-headed dog on the third-floor corridor. As a result, Harry and Ron begin to believe this is because he is trying to get past the creature to the trapdoor underneath. He also appears to be trying to jinx Harry off his broom during the Gryffindor versus Slytherin Quidditch match, which finally convinces Hermione that he is up to something.

Discovered in chapter 13
Nicolas Flamel
In the spring, Professor Snape threatens Professor Quirrell, trying to find out if he knows how to get past Fluffy. He warns Professor Quirrell not to make him into an enemy.

Discovered chapter 18

The Man with Two Faces
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Professor Snape was not, as Harry initially thought, the person who was trying to steal the Philosopher’s Stone or jinx Harry off his broom. He was trying to protect the Stone by intimidating Professor Quirrell and was attempting to save Harry’s life by muttering a counter to Professor Quirrell’s jinx during the Quidditch match.

At the end of the year Professor Snape’s feelings toward Harry don’t seem to have changed one bit.