Murderer Sirius Black escapes from a prison no one has ever escaped from, and he wants Harry. Why? Even the Dementors, the Azkaban guards now protect Hogwarts, seem malevolent to Harry. School is supposed to be safe, but Harry, who never trusted his Muggle relatives, learns that sometimes even his Hogwarts family can withhold the truth.

— Kathleen Hennrikus, Globe Staff