Harry Potter and the Half Blood Prince2009

Horace Slughorn:
Some of your classmates... well, let's just say they're unlikely to make the shelf.

Harry:
Shelf, sir?

[Slughorn points to a wall of portraits of his favorite students.]

Horace Slughorn:
Anyone who aspires to be anyone ends up here. But then again, you already are someone, aren't you, Harry?

Harry:
Did Voldemort ever make the shelf, sir? [Slughorn freezes] You knew him, didn't you, sir? Tom Riddle? You were his teacher.

Horace Slughorn:
Mr. Riddle had a number of teachers whilst he was here at Hogwarts.

Harry:
What was he like? [no response] I'm sorry, sir. Forgive me. He killed my parents.

Horace Slughorn:
I... of course, it's only natural you should want to know more. But I'm afraid I must disappoint you, Harry. When I first met young Mr. Riddle, he was a quiet, albeit brilliant boy committed to becoming a first-rate wizard. Not unlike others I've known. Not unlike yourself, in fact. If the monster existed, it was buried deep within.