Harry Potter and the Prisoner of Azkaban, Book 3 Audiobook
There is the news that Sirius Black has escaped from Azkaban and he happens to be the first man who escaped from this heavily guarded prison. Sirius is said to be an ally of Voldemort and he is coming for Harry Potter. When Harry reaches Hogwarts he starts hearing more troubling news than ever..[Harry Potter and the Prisoner of Azkaban, Book 3 Audiobook ]
The Dementors are hovering over the school which means that the dark lord has finally decided to come back. J.K. Rowling makes the series, a serious one from this third chapter onward. The enemies are finally present in the open and they are gathering power for the final and perhaps last confrontation. Harry makes a new friend in the form of Sirius here after he learns his true identity.