For those who don't know, the Harry Potter series consists of 7 books. They are basically about a boy named Harry Potter who lives with his abusive aunt and uncle until he turns 11 and learns that he is a wizard and is taken to a special school called Hogwarts to learn about magic. When he grows up, he learns that he is destined to kill Voldemort, the most evil wizard ever.
The reason I gave the Sorcerer's Stone 10/10 is that it has all the elements of a great book. The story follows Harry, who is taken to Hogwarts and makes 2 friends, Ron and Hermione. Harry also makes an enemy, Professor Snape. For some reason, he seems to hate Harry. Then they discover that Professor Quirrel, another teacher, is being possesed by Voldemort, who does not have a body, though he regains it later on in the series. Towards the end of the series, Quirrel (Voldemort) attempts to steal the Sorcerer's Stone from Hogwarts. It is a stone that provides an elixir of immortality. Harry battles Quirrel and Quirrel ends up dead, and Voldemort is once again without a body to posses.