Harry Potter/Harry Potter and the Deathly Hallows/Recap/C 33 The Princes Tale

While Harry is still at Snape's side, Voldemort speaks to Hogwarts in a magically magnified voice. He orders his forces to retreat and gives Harry one hour to hand himself over in the Forbidden Forest, where Voldie will be waiting. If Harry doesn't show, the battle will resume with Voldemort himself joining in. The Trio heads up to the battle-scarred Hogwarts and finds everyone in the Great Hall, where the injured are being treated and the dead have been laid for now. Ron and Hermione join the Weasleys, who are mourning Fred. Harry sees the bodies of Lupin and Tonks, both of whom had bridges dropped on them. Blaming himself for all the death, Harry slips away to Dumbledore's office. He takes out the Pensieve, inserts the memories Snape gave him, and dives in.

In the first Pensieve Flashback, Harry sees a preteen Snape watching two girls on a playground. They turn out to be Lily and Petunia. Lily is freaking Petunia out be doing some simple magic, though it's obvious Petunia is really jealous. Snape comes out and says that Lily is a witch, but the girls don't believe him and Petunia acts snobby. In the next scene, Harry sees Lily and Snape hanging out. Snape describes Hogwarts, how his parents argue all the time, and the dementors of Azkaban. But then they notice Petunia is spying on them. An astue reader will realize Snape was the "awful boy" Petunia overheard talking about dementors. Next Harry sees them at Platform Nine-and-Three-Quarters. It seems Petunia wrote to Dumbledore asking if she could go, but, of course, she couldn't and now she's adopted her adult viewpoint of seeing magical people as "freaks". After covering Snape and Lily's arrival at Hogwarts, the memory skips ahead several years. Lily is upset that Snape's friends are evil and he responds by complaining about the Marauders. She agrees that the Marauders suck, but argues that Snape's friends are far worse. Then Harry reexperiences the memory he saw back in his fifth year, but now he sees the aftermath. Snape tries to apologize for what he said, but Lily won't let him. She explains that she's put up with his crap for years, but this is the last straw and now they aren't friends anymore.

Next Harry sees an adult Snape meeting Dumbledore on a dark hill at night. Snape tells Dumbledore that Voldemort has figured out Trelawney's prophecy refers to Lily's son. Snape wants to Save The Girl and, it's implied, this is the moment he becomes Dumbledore's spy. In the following scene, Snape is angry that Lily is dead. Dumbledore tells him that he should help protect Harry so that Lily won't have died in vain. Snape agrees, but makes Dumbledore promise never to tell anyone. The rest of the scenes take place during the time frame of the series and there's a Call Back to the first book in which Dumbledore tells Snape to keep an eye on Quirrell. A couple memories later, it's revealed that Dumbledore was dying from the moment he touched Marvolo Gaunt's ring. In order to avoid the painful death which the ring's curse would have eventually caused, Dumbledore asked Snape to Mercy Kill him at a strategically advantageous moment, creating a Thanatos Gambit. Then we get to The Reveal. The big one. Yes, even bigger than that last one. Voldemort accidentally turned Harry into a Horcrux the night he failed to kill him as a baby. This is why Harry can speak Parseltongue and has a connection to Voldemort's mind. But Voldemort cannot die as long as the piece of his soul inside Harry lives. Harry will have to sacrifice himself to Voldemort. Of course, Snape is aghast that he's been utterly manipulated. All these years he's worked for Dumbledore with the understanding that it was all to protect Lily's son, but now he learns that Dumbledore ultimately intended for Harry to die. Snape reveals that his Patronus has always been a silver doe. He has remained in love with Lily all these years because Unrequited Love Lasts Forever. After Dumbledore's death, Snape takes to consulting with Dumbledore's portrait in the headmaster's office. Snape plants the idea of decoys in Mundungus's head using a Confundus Charm and only severed George's ear by accident. And Snape, it turns out, was the one who placed Godric Gryffindor's sword in the frozen lake for Harry to find.

At this point, Harry is spat out of the Pensieve.