My favorite prologue to a book was in J.K. Rowling's Harry Potter and the Philosopher's Stone. When I read it for the first time, it wrapped me up in a sense of intrigue and magic.
The book begins in a dramatic fashion, with a description of a muggle who, when exasperated attempts to dispose of an old gift given to him by his dead brother, an invisibility cloak. The muggle encounters three wizards who have come to take a baby who, unbeknownst to the muggle, is the titular character, Harry Potter.
The three wizards then travel to a large, decrepit house where a mysterious being known as Dumbledore is waiting. He speaks in a matter-of-fact fashion, revealing the prophecy of Harry Potter's destiny: he is destined to take on the sinister Voldemort and save the wizarding world. This line of dialogue serves to draw the reader in, ensuring that we quickly become engaged with the story.
The prologue ends with a powerful question by Dumbledore, that lingers in the readers minds even after the prologue is complete: “Is it a coincidence that you [the reader] came to this page?”
Simply put, the prologue of Harry Potter and the Philosopher's Stone was masterfully crafted to draw the reader in and capture our imagination. Through its subtle hints, the prologue acts as an effective introduction to the world of Harry Potter that many have grown to love.