My understanding was Lucius came home and "found" Narcissa burned in the remnants of the house, or at least remembered doing so. It just doesn't make sense that a clever, cunning man (who brought Draco to see Death Note and criticized the plot) would find no trace of his wife and, knowing Dumbledore to be famously soft-hearted, would just unquestioningly believe that story.
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 120.
Plans for next chapter release:
There is a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.)