Whatever critics have thought of the new Harry Potter movie, they've agreed on one thing: It's a remarkably faithful adaptation. But even at more than two and a half hours, it compresses or leaves out key scenes and details, and anyone who hasn't read the book (all dozen of you) may have trouble following all the ins and outs. Hence, a guide to some of the movie's more puzzling questions. (Plot Holes habitually gives away crucial bits of the story, so quit reading now if you don't want to know.)
Who are the two goons that Draco Malfoy—the snotty blond kid—introduces at Hogwarts?
Crabbe and Goyle, who serve as Malfoy's henchmen. They do play a bigger part in the book, mostly in scenes that didn't make it into the movie. The filmmakers probably figured the book fans in the audience would expect to at least see them.
Why does that library book scream at Harry?
Actually, the book doesn't explain this one either. Maybe it's a spell designed to protect whatever is in the book. Or maybe Rowling simply needs a plot device to get Harry out of the library.
Where does Harry's invisibility cloak come from?
Harry receives a mysterious Christmas present—a cloak that makes its wearer invisible—and attached to the parcel is an unsigned note explaining that the cloak once belonged to Harry's late father. It seems like a setup for a later scene, in which Harry's benefactor is dramatically revealed. But the payoff never comes. Near the movie's climax, Harry and his friends use it to sneak into the room with the three-headed dog, then drop it—and we never see it again. (And no, it's not called an invisibility cloak because it disappears without explanation.)
As the book explains, it turns out that the school's kindly headmaster, Albus Dumbledore, gave Harry the cloak. But like the movie, Rowling doesn't say what happens to it after Harry drops it.
Why is Ron riding that knight during the life-size chess match?
On their way to stop an evil wizard, Harry and his friends Ron and Hermione find themselves on a life-size chessboard and realize that, to continue their quest, they have to play out the match themselves. It's a scary proposition, because when a piece is taken in wizard chess, it's not just removed from the board; it gets smashed to bits. Harry and Hermione, subbing for a bishop and a rook, stand on the board as Ron directs them to various squares. Ron, though, mounts a knight, which he's thrown from when it's crushed by the opposing queen. Why doesn't he hop off the horse before the queen smashes it?
The filmmakers pretty much botch this scene. In the book, Ron learns from one of the chess pieces (they're magical, remember) that each young wizard has to stand in for a piece. Then—here's the crucial thing the movie leaves out—the replaced pieces walk off the board. Ron isn't riding the knight; he is the knight. Harry and Hermione play by the rules of the book—they substitute for other pieces—but the movie makes up a new rule for Ron.
Presumably, screenwriter Steven Kloves rewrote the scene because what happens in the book is pretty gruesome and doesn't reflect especially well on Harry. The queen hits Ron hard on the head and drags his unconscious body off the chess board. Harry basically glances at Ron, says unconvincingly, "He'll be all right," and gets Hermione to move along to the next puzzle. In the movie, Harry tells Hermione to stay behind and tend to their friend, which makes him seem more compassionate.