Although PoA is not one of the longest books of the series or even one that has one of the most action packed sequences, it remains one of my favorites because it introduces someone who could arguably be my favorite HP character of all time.  Sirius Black.  A troubled soul, tormented for years in an Azkaban jail.  Ends up spending a year living off rats so he can stay clear of the ministry of magic and stay alive to see Harry again.  He was good looking but didn't recognize it from what JKR has told us.  And most of all

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he dies one of the most heroic deaths.  Some might...