“Harry Potter and the Deathly Hallows” (Scholastic, 784 pages, $34.99), the last of seven books in J.K. Rowling’s blockbuster series, is one of the most eagerly anticipated novels in history. Each of the first six novels details a year of Harry Potter’s life as a student at the Hogwarts School of Witchcraft and Wizardry. Adolescence is a turbulent time for everyone, but Harry has had a particularly tough time, as he is widely believed to be the one wizard who has a shot at defeating the evil Lord Voldemort. Harry escaped Voldemort and his loyal Death Eaters in the first six books, but now he will have to confront the “Dark Lord” once and for all. More than 300 million copies of the first six books have been sold worldwide, and millions of fans are awaiting the final showdown.

Scholastic, Ms. Rowling’s American publisher, has gone to great lengths to keep the book under wraps until it goes on sale at 12:01 a.m. thisSaturday. Printing presses are on high alert, and review copies were not mailed out until Monday. So far, the precautions have worked. No major spoilers have surfaced.

This is excellent for fans of the series. No one has ruined the ending and no one has ruined the fun of speculating. Readers are reeling with questions. Is Severus Snape really a bad guy? Is Minerva McGonagall a spy? Will Harry survive? Will Ron and Hermione end up in Smooch City?

The following predictions will be unintelligible to those who are not familiar with Harry’s adventures these past 10 years. But just in case, please be advised that they contain spoilers about the books that are already published.

1. Snape Is Good.

Severus Snape has always seemed like a villain. He hates Harry Potter. He pals around with Death Eaters. He has a long, sallow face and greasy hair. He used to work for Lord Voldemort but was later accepted into the Order of the Phoenix, mostly on the strength of Albus Dumbledore’s trust in him. Snape’s idea of returning the favor was to kill Dumbledore at the end of the sixth book, “Harry Potter and the Half-Blood Prince.”

Snape is so obviously bad that we’re forced to assume he is secretly good. There must be some reason Dumbledore trusted him despite all available evidence. Perhaps the two of them made an Unbreakable Vow to protect Harry Potter. Snape will make his true allegiance known in “The Deathly Hallows,” and may well die in the process.

2. Ron and Hermione Will Live.

Last year, Ms. Rowling said in an interview that at least two characters will die in “The Deathly Hallows.” Fans are anxious that Harry’s best friends, Ron Weasley and Hermione Granger, will end up among the dead.

This is unlikely. In previous books, major deaths advanced the plot. For example, the deaths of Harry’s two fiercest protectors — Dumbledore and Sirius Black — set him up to face Voldemort alone in the final book. The shocker in “Harry Potter and the Goblet of Fire,” the murder of Cedric Diggory, had served a practical purpose for Ms. Rowling. It signaled to readers that there would be serious business ahead. But there is no good reason for Ms. Rowling to kill off Ron and Hermione. Doing so would only traumatize readers. And there’s no evidence that either of the two is marked for death. They may be Harry’s best friends, but they are small potatoes to the Death Eaters. They may make themselves vulnerable by getting trampled underfoot, but should scrape through safely to the end.

So who will die? Look for one of the “bad” guys — Snape, Draco Malfoy, or perhaps Percy Weasley — to redeem himself with a well-timed death. The Order of the Phoenix will sustain losses among its second-tier characters. And poor Neville Longbottom ought to keep his wits about him.

3. Harry Will Live, too.

Some British bookies have stopped taking bets on whether Harry Potter will survive “The Deathly Hallows,” because so many people are betting against him. And it’s worth considering the prospect of Harry’s death, simply because it would be such a bold move for Ms. Rowling.

Fans are also worried for Harry because Ms. Rowling has expressed sympathy for writers who kill their characters as way of ending their adventures. But she would find it difficult to really kill Harry. Dead wizards turn up as ghosts, in portraits, and in magical mirrors. Ms. Rowling insists that Dumbledore is dead, and yet legions of fans insist that he simply cast a very powerful death-looking spell on himself. It would be simpler, and more cheerful, to let Harry live — and that’s what will most likely happen.

4. Lily Potter Was a Death eater.

Ms. Rowling has said that we will discover something “incredibly important” about Harry’s mother, Lily, in “The Deathly Hallows.” We may now discover she was a Death Eater, spying on the Order of the Phoenix and even on her own husband. We know suspiciously little about Lily Potter. Voldemort, who seldom hesitates to kill, gave her a chance to step aside before he killed her. Her non-magical sister, Petunia, is frightened of wizardry. In her youth, Lily was a defender of Snape. The most important thing we know about her is that she died in an effort to protect the infant Harry. But that does not prove whose side she was on. Even a villain may love her children.

The evidence against her is entirely circumstantial and the idea is admittedly farfetched, but it is morally appealing. Harry Potter has never questioned his allegiance to the good side. He was born into it. Yet Ms. Rowling repeatedly makes the point in the books that choices make the wizard, not accidents of birth. A painful truth about his mother would force Harry to examine his own soul and act according to its directives.