Harry Potter and the Half-Blood Prince

Chapter by Chapter

Chapter One - The Other Minister
(Reader's Guide to Chapter 1)

In which the Muggle Prime Minister recounts his encounters with Cornelius Fudge, Fudge visits him again with Scrimgeour, and we learn that Scrimgeour is the new Minister of Magic. We also hear of the wizarding world's open war with Voldemort - dozens of Muggles have been killed along with Amelia Bones and Emmeline Vance, the dementors and giants have joined Voldemort, and the Ministry is struggling to fight.

In which Narcissa goes to visit Snape in secret against Voldemort's orders, and Bellatrix tries to stop her but joins her at Snape's house anyway. Snape prevents Wormtail's eavesdropping and tells Bellatrix his story, though she still refuses to trust him; Narcissa then reveals that Voldemort has ordered Draco to do something difficult, and asks Snape to make an Unbreakable Vow - which he then does, saying that he will help Draco carry out the deed, and perform the deed himself if Draco fails.

Chapter Three - Will and Won't
(Reader's Guide to Chapter 3)

In which the Daily Prophet tells us about the wizarding public's perception of Harry and the steps the Ministry has taken to provide safety in the war, and Dumbledore returns to Privet Drive. Before leaving, Dumbledore sits with Harry and the Dursleys, updates Harry on his inheritance from Sirius and gives him Kreacher, determining that he has indeed come into Harry's possession. Dumbledore then chastises the Dursleys for their treatment of Harry but asks that he be allowed to return to Privet Drive one final time, and he and Harry depart.

Chapter Four - Horace Slughorn
(Reader's Guide to Chapter 4)

In which Harry and Dumbledore apparate to Budleigh Blabberton - discussing Voldemort, Inferi, and Dumbledore's injured hand along the way - and meet Slughorn, shortly after he has faked his own demise. Dumbledore asks Slughorn to teach at Hogwarts, and Harry convinces him to while Dumbledore is out of the room. Dumbledore then takes Harry to the Burrow, where before entering he tells Harry about Slughorn, talks to him about Sirius and the prophecy, and tells Harry he will be taking private lessons from Dumbledore during the school year.

Chapter Five - An Excess of Phlegm
(Reader's Guide to Chapter 5)

In which Harry talks with Mrs. Weasley (and later Mr. Weasley) about the Ministry, we see Fleur and learn that she and Bill are engaged to his family's dismay, and Harry tells Ron and Hermione about Slughorn, his private lessons with Dumbledore, and the prophecy, while they tell him about Fleur and Tonks. O.W.L. results then arrive, with Harry earning seven O.W.L.s but realizing that Snape won't allow him to take N.E.W.T. potions, and therefore he won't be able to become an Auror.

Chapter Six - Draco's Detour
(Reader's Guide to Chapter 6)

In which we learn of several disappearances including Florean Fortescue and Mr. Ollivander, and Harry, Hermione, and the Weasleys go shopping at Diagon Alley, escorted by Hagrid.  There they discover a much-changed atmosphere and an empty Leaky Cauldron, have a run-in with Draco and Narcissa Malfoy in Madam Malkin's, tour Weasleys' Wizard Wheezes, and sneak out to follow Draco into Borgin and Burke's, where they overhear a mysterious conversation between him and Mr. Borgin.

Chapter Seven - The Slug Club
(Reader's Guide to Chapter 7)

In which Harry thinks Malfoy might be a Death Eater, everyone departs for King's Cross, and before getting on the train Harry tells Mr. Weasley his suspicions. On the train, Harry finds he is more famous than ever, but sits with Neville and Luna until Slughorn invites him to tea. After hours of boring conversation, Harry sneaks into the Slytherins' compartment, invisible, and listens to Malfoy brag about working with Voldemort, but when the train stops Malfoy freezes Harry and leaves him behind.

Chapter Eight - Snape Victorious
(Reader's Guide to Chapter 8)

In which Tonks rescues Harry from the train and Snape leads Harry in to the feast, criticizing Harry all the way. Once inside, Harry discusses his status as 'The Chosen One' with those around him and Dumbledore gives his opening speech, announcing that Slughorn will be teaching Potions and Snape teaching Defense Against the Dark Arts. On the way out of the hall, Harry and Ron discuss Malfoy and run into Hagrid, who tells them about Grawp and leaves them feeling guilty for not taking his class.

Chapter Nine - The Half-Blood Prince
(Reader's Guide to Chapter 9)

In which Gryffindors get course schedules and discuss Malfoy and Quidditch trials, then go to their first day of classes. In Defense Against the Dark Arts Harry fights back against Snape's attempt to jinx him and gets detention, during break he hears his first lesson with Dumbledore will be Saturday, and in Potions Harry wins the Felix Felicius thanks to a perfect potion he brewed with the instructions written in his book by the Half-Blood Prince.

Chapter Ten - The House of Gaunt
(Reader's Guide to Chapter 10)

In which Harry attends his first lesson with Dumbledore, who explains that they will be delving into Voldemort's past and takes Harry into the pensieve. In Bob Ogden's memory they go to Marvolo Gaunt's house to see about his son, Morfin, who has committed a crime; there they see a mean, impoverished, racist Marvolo abusing his daughter Merope, who is watching Muggle Tom Riddle. Dumbledore explains that Merope later used a love potion on Tom, and they became Voldemort's parents.

Chapter Eleven - Hermione's Helping Hand
(Reader's Guide to Chapter 11)

In which Harry discovers his newfound popularity, learns that Stan Shunpike has been arrested, and holds a frustratingly massive Quidditch tryout that includes a run-in with Cormac McLaggen and Katie, Ginny, and Ron making the team. They visit Hagrid and learn that Aragog is dying, Harry confronts Hermione about having confunded McLaggen during the tryout, and Slughorn invites Harry and Hermione to supper, but Harry is spared having to go when Snape refuses to let him out of detention.

Chapter Twelve - Silver and Opals
(Reader's Guide to Chapter 12)

In which Harry tries one of the Half-Blood Prince's spells while reading in bed and levitates Ron by accident, argues with Hermione over the danger of the Prince, and gets word of his next lesson with Dumbledore. The trio then walks to Hogsmeade, where Slughorn corners Harry in Honeydukes and Harry sees Mundungus with things stolen from Grimmauld Place. On the way home, an Imperiused Katie Bell touches a cursed necklace and is hurt; Harry then suspects Draco and tells McGonagall this, though Ron and Hermione don't believe him.

Chapter Thirteen - The Secret Riddle
(Reader's Guide to Chapter 13)

In which Harry has his second lesson with Dumbledore, where they briefly discuss Mundungus and Draco, and Dumbledore discusses Merope with Harry again. Together, they then view a memory of Dumbledore's, where he visits Voldemort's childhood orphanage to invite him to school. In it, Dumbledore learns Riddle's history and discovers that he has already been using magic, hates his name, likes to steal and collect trinkets, and neither has nor desires friends.

Chapter Fourteen - Felix Felicis
(Reader's Guide to Chapter 14)

In which Hermione and Ron discuss the Slug Club in Herbology and Harry notices an attraction between them, Dean takes Katie's place on the Quidditch team, and Harry and Ron run into Ginny and Dean kissing. Ron gets upset and Ginny tells him off, but Harry starts thinking of kissing Ginny himself. Ron becomes angry and plays terribly next practice, but for the match Harry pretends to slip him Felix Felicis, giving him confidence, and Gryffindor wins. After the game, Ron is spotted kissing Lavender, leaving Hermione upset.

Chapter Fifteen - The Unbreakable Vow
(Reader's Guide to Chapter 15)

In which Hermione stays angry with Ron but Harry tries to stay friends with both, Harry finds that girls are trying to seduce him, and Romilda Vane tries to slip him a Love Potion. Harry then asks Luna to Slughorn's Christmas party, and Hermione invites McLaggen to upset Ron. After some general mingling at the party, Malfoy is caught prowling the corridors and Snape takes him away to an empty classroom, where Harry overhears Snape's offers to help Malfoy and Draco's refusals.

Chapter Sixteen - A Very Frosty Christmas
(Reader's Guide to Chapter 16)

In which Harry and Ron discuss Malfoy and Snape, Harry tells Mr. Weasley his suspicions and hears about the Ministry's poor fight against Death Eaters, Lupin talks about Snape and Greyback, and Harry discovers that the Half-Blood Prince's book was fifty years old. Percy shows up on Christmas with Scrimgeour, who then asks Harry to support the Ministry, and Harry refuses strongly, saying he disapproves of the actions the Ministry has been taking.

Chapter Seventeen - A Sluggish Memory
(Reader's Guide to Chapter 17)

In which, back at Hogwarts, Harry chats with Hermione about Ron and Malfoy, learns that apparition lessons are coming, and finds that both Ron and Ginny seem disenchanted with their relationships. He then has a lesson with Dumbledore, where they discuss Scrimgeour and see two memories: in the first, Morfin tells Voldemort about his family just before Voldemort kills the Riddles; in the second (which Slughorn has modified), Voldemort asks Slughorn about horcruxes. Finally, Dumbledore sets Harry homework - to obtain the rest of Slughorn's memory.

Chapter Eighteen - Birthday Surprises
(Reader's Guide to Chapter 18)

In which Harry gives Slughorn a bezoar instead of an antidote in Potions class, then asks him unsuccessfully about Horcruxes. The sixth-years then have their first apparition lesson, where Harry overhears Malfoy saying Crabbe has been acting as his lookout, and Harry starts watching the Marauder's Map. Then, on Ron's birthday, Ron accidentally consumes Romilda Vane's love potion and Harry takes him to Slughorn to get an antidote; there, Slughorn gives Ron some poisoned mead and Harry saves his life with a bezoar.

Chapter Nineteen - Elf Tails
(Reader's Guide to Chapter 19)

In which Harry discusses Ron's poisioning with the Weasleys, Hagrid tells Harry that he overheard Dumbledore and Snape arguing, McLaggen accosts Harry to ensure he can play in Ron's place in the upcoming Quidditch match, and Harry finds that Ron has been avoiding Lavender. At the Quidditch match (with Luna commentating!), McLaggen grabs a beater's bat and cracks Harry's skull. Finally, in the hospital wing, Harry summons Kreacher and Dobby and orders them to tail Malfoy and figure out what he's up to.

Chapter Twenty - Lord Voldemort's Request
(Reader's Guide to Chapter 20)

In which Ginny fights with Dean and Ron with Lavender, Luna delivers a message to Harry of a lesson with Dumbledore, and Harry arrives at the lesson to find Trelawney being asked to leave. Dumbledore makes Harry feel guilty for not procuring Slughorn's memory, but they view two new memories: in the first, Riddle visits Hepzibah Smith and sees Slytherin's locket days before her death; in the second, Riddle asks Dumbledore for the D.A.D.A. post at Hogwarts, which Dumbledore admits began the curse on the position.

Chapter Twenty-One - The Unknowable Room
(Reader's Guide to Chapter 21)

In which Harry talks with Ron and Hermione about Apparition, Slughorn's memory, and Lavender, and Kreacher and Dobby show up to report on Malfoy, making Harry realize Draco's been using the Room of Requirement with Polyjuiced Crabbe and Goyle as lookouts. Harry spends some time trying to get into the Room of Requirement (unsuccessfully), Snape picks on him in class again, Moaning Myrtle reveals she's been talking with a boy, and Harry runs into a disheveled Tonks and wonders if she loved Sirius.

In which Aragog dies, Ron and Hermione have their Apparition test, and Harry makes a Euphoria potion in a class with just Slughorn, Ernie and Draco, after which he tries to corner Slughorn but fails.  Hermione passes her test and convinces Harry to take Felix Felicis to get Slughorn's memory; Harry does, and goes down to Hagrid's, meeting and inviting Slughorn along the way. There they bury Aragog together, Slughorn and Hagrid become drunk, and Harry convinces Slughorn to give him the memory.

Chapter Twenty-Three - Horcruxes
(Reader's Guide to Chapter 23)

In which Harry learns that Dumbledore has returned, races off to his office, and with him watches Slughorn's memory, where Riddle learns what Horcruxes are and contemplates making more than one.  Dumbledore explains his suspicions that Riddle made six, including the now-destroyed ring and diary, the locket, the cup, and Nagini.  Dumbledore promises Harry can join him in destroying the next one, and explains to Harry what love - and the prophecy - really mean.

Chapter Twenty-Four - Sectumsempra
(Reader's Guide to Chapter 24)

In which Ron and Ginny are both single again, Katie Bell returns to Hogwarts but can't remember what happened to her, and Harry sees Malfoy with Moaning Myrtle on the Marauder's Map and runs to eavesdrop - but when Malfoy tries to hex Harry, Harry uses the Sectumsempra on him without knowing what it does and slashes him apart. Snape heals Malfoy but gives Harry detention during the Quidditch match, which Gryffindor wins anyway. Then, when Harry arrives at the party, he finally kisses Ginny.

Chapter Twenty-Seven - The Lightning-Struck Tower

In which Harry and Dumbledore return to Hogsmeade and see the Dark Mark over Hogwarts. They fly to the top of the astronomy tower, where Draco appears and disarms Dumbledore, but can't bring himself to kill him and Dumbledore tries to convince Draco to come to the good side. Before Malfoy can decide, though, other Death Eaters show up - including Snape, who kills Dumbledore himself, blasting the body off of the tower.

Chapter Twenty-Eight - Flight of the Prince
(Reader's Guide to Chapter 28)

In which Snape, Malfoy, and the Death Eaters flee, and Harry gives chase. On the way, he runs through a raging battle involving the Order and tries unsuccessfully to curse Snape (who we learn definitively is the Half-Blood Prince), Hagrid's hut is set ablaze and the Death Eaters escape. Harry and Hagrid then put out the fire, see students all over the grounds, and find Dumbledore's body.  Harry also discovers that the locket was not a real Horcrux, but a replacement put there by the person who took the real one: R.A.B.

Chapter Twenty-Nine - The Phoenix Lament
(Reader's Guide to Chapter 29)

In which Ginny leads Harry to the hospital wing, where the Order discusses Bill, Dumbledore, Snape, and the events of the evening. We also learn that Fleur still wants to marry a disfigured Bill, and that Lupin has been refusing dates with Tonks. McGonagall takes Harry to her office (formerly Dumbledore's) and asks where he was but Harry refuses to say; the heads of houses then arrive and discuss closing the school. Finally, as Scrimgeour arrives, Harry leaves to Gryffindor Tower, where he updates Ron on the Horcrux.

Chapter Thirty - The White Tomb
(Reader's Guide to Chapter 30)

In which most students hang around for Dumbledore's funeral, as wizards from across the country flood in to pay their last respects.  Hermione discovers that Eileen Prince was Snape's mother, Harry ponders the Horcruxes a bit, and then all attend the funeral, after which Harry breaks up with Ginny. As Harry then walks off on his own, Scrimgeour again tries to persuade him to help the ministry, and Ron and Hermione come over. Harry tells them he won't return to Hogwarts, and they pledge to stay by his side.