What really happened to Draco's mother (Narcissa) in Methods of Rationality?

Question

I'm confused about the story of Draco Malfoy's mother Narcissa Black in Harry Potter and the Methods of Rationality.

In chapter 47, Harry learns that Draco says that Draco's stepfather Macnair says that Draco's father Lucius says that Headmaster Dumbledore has burned Draco Malfoy's mother alive in her own bedroom. That chapter also says that Draco's mother is called Narcissa (the same given name as in Harry Potter). This sounds like an important plot point so the truth about this has to be revealed later.

This isn't resolved until close to the end of the book, in chapter 120 titled “Something to Protect: Draco Malfoy”. I am, however, very confused about that resolution, since it leaves a lot of things implicit. Let me first recap what the chapter says explicitly.

That chapter first mentions that there existed a letter with secret instructions for the ultimate weapon to destroy Lucius, if his political power gets so dangerous to the Order that there is no other way to fight him, but that this weapon should not be used “until the whole war hung in the balance”.

We then see a woman named Nancy Manson regain her true memories. She has lived as a Muggle for ten years, but now she remembers she was a witch. Her memories are awoken by a Scottish witch, and she sees a “boy, with short white-blonde hair and wearing […] dark robes trimmed in green, staring at her with his jaw dropped and eyes wide and beginning to fill with tears”. Nancy says the name “Lucius” in the end. The chapter also mentions that Nancy had a dream to move to Australia.

Here's what I surmise from this.

• The boy with the white-blonde hair is presumably Draco, since this is a chapter about Draco. But the short hair confuses me, because I have an image of Draco with long hair from the Harry Potter films.
• Nancy is presumably Narcissa, since they have a similar name, Narcissa's story wasn't resolved up to then, and Draco finding her mother would certainly make her eyes fill with tears.
• I presume the Scottish witch was Professor McGonagall.
• Someone has hidden Narcissa to protect her after the Dark Lord has first fallen.
• This plot element may be a nod to how Professor Dumbledore offers Draco to hide him and his mother from the wrath of the Dark Lord in Half-Blood Prince chapter 27.
• Hiding someone by erasing her memory is clearly a nod at how Hermione hides her parents from the final stage of the wizarding war in Harry Potter, especially with that mention of moving to Australia.
• The story about Professor Dumbledore burning Narcissa alive was false, although Draco has honestly believed it. Either Lucius has invented the story, or he had it as a false memory, or perhaps Macnair has lied.
• The letter tells that Narcissa is alive and hidden, so the ultimate weapon is holding her hostage and blackmailing Lucius.

Are these points correct? Even if they are, there is still a lot unanswered. In particular, who has arranged to hide Narcissa this way? If it was Lucius himself, the Order couldn't know about this, so the letter wouldn't exist. But if it was Professor Dumbledore, then who invented the story that he has tortured the innocent Narcissa in that terrible way? Such a story sounds like a politically stupid move for Dumbledore. Further, what did Lucius himself believe about his wife?

I'm sorry if the above sounds like multiple questions, but really I just have one overall question: what's the true story of Draco's mother Narcissa?

Answer 1

Your presumptions are correct. Dumbledore put on a show of murdering Narcissa.

At some point during the Wizarding War, the Death Eaters began going after families. Dumbledore's brother was held hostage and tortured to death under the Cruciatus Curse. In response, Dumbledore "killed" Narcissa.

"Do you also wish to see my brother as he died under the Cruciatus?" said Albus Dumbledore. "Voldemort sent me that memory as well!"

"And that - " Harry was having trouble producing a voice, for the growing sickness in his chest. "That was when -" The words seemed to burn in his throat, as the awful knowledge dawned on him, the horrible understanding. "That was when you burned Narcissa Malfoy alive in her own bedroom."

Albus Dumbledore's gaze was cold as he answered. "To that question only a fool would say yea or nay. What matters is that the Death Eaters believe I killed her, and that belief kept safe the families of all who served the Order of the Phoenix - until this day. Now do you understand what you have done? What you have done to your friends, Harry Potter, and to any that stand with you?" The old wizard seemed to grow still taller and more terrible, as his voice rose louder. "You have made them all targets, and targets they will remain! Until you prove, the only way it can be proven, that you are no longer willing to pay such prices!"

"And is it true?" Harry said. There was a buzzing sensation filling him, his body growing more distant. "What Draco said, that Narcissa Malfoy never got her hands dirty, that she was only Lucius's wife? She was an enabler, I get that, but I can't back that deserving being burned alive."

"Nothing less would have convinced them that I was done with hesitation." The old wizard's voice brooked no question and no refusal. "Always I was too reluctant to do as I must, always it was others who paid the cost of my mercy. So Alastor told me from the beginning, but I did not listen to him. You, I expect, shall prove better at such decisions than I." (Chapter 82)

Because of Dumbledore's response, the Death Eaters realized they had nothing to gain and a lot to lose by continuing to go after other people's families. So, they stopped. That's why Dumbledore did it.

There is no indication anyone other than Dumbledore knows Narcissa is alive, especially Lucius. Lucius was one of the people Dumbledore had to stop from doing this ever again. It would completely defeat Dumbledore's purpose if Lucius knew.

That Narcissa was actually saved was foreshadowed here, and when Harry first met Dumbledore.

"I didn't know about Fawkes," Harry's voice said rapidly, "so he told me that Fawkes was a phoenix, while he was pointing to a chicken on Fawkes's stand so I'd think that was Fawkes, and then he set the chicken on fire - and also he gave me this big rock and told me it had belonged to my father and I ought to carry it everywhere -" (Chapter 70)

Dumbledore describes it in his letter to Harry as:

"Here's the last thing," Harry Potter said. "I found it in a folded parchment whose outside said that it was the last weapon to be used against House Malfoy, telling me not to read any further until the whole war hung in the balance. I didn't want to tell it to you before because I thought it might prejudice your decision unfairly. If you were a good person who never killed or lied, but you had to do one or the other, which would be worse?" (Chapter 120)

...which confirms for us Lucius definitely did not know. If Lucius was already being blackmailed, it would not be the "last weapon" to use against House Malfoy: it's a rabbit you pull out of a hat when there's nothing left, which comes with some risk, because it shows you were never really willing to retaliate in kind after all.