Warning: Here be spoilers
In Chapter 4, Nancy goes through her first day of school, and wakes up on her second to find her roommate murdered. After learning more of Jack and Jill’s travels, Nancy helps Kade and Jack clean up Sumi’s things.

Character

“The worlds we experienced barely seemed to match up, despite being the same place,” said Jack.

The past few chapters I’ve been saying that the worlds are almost equivalent to each person’s character, but here we have the counterargument. We hear both Jack and Jill describe their world and how they came to leave it, and they are very different accounts. Some parts match, but the way they describe it is different – Jill goes on about the “so many beautiful, wonderful things” she was taught, whereas Jack gives details of what she was taught (the ways of recombining and reanimating tissue). The stories of how they left also don’t match up – we’ll find out why later. The story is quite adamant that these are different people, even though they are twins. We can see this if we go back to when they were first introduced – the description there remarks on how differently they wore the same face.

This, in its way, is an exploration of how characters can differ. Jack and Jill are similar in situation. They were born into the same family, underwent the same trials and were both forced into roles they did not want. However, they are distinct people, and their world allowed them to realise this truth, and explore their differences.

Theme

“Nancy realised that Sumi’s granddaughter was never going to visit the candy corn farmer’s grave, and it took everything she had not to weep for what had been irrevocably lost.”

There are many examples of external narratives being forced on others in this chapter. Jack and Jill’s parent’s wove their narrative of ‘the smart one’ and ‘the pretty one,’ and Jack and Jill suffered for that. We see a glimpse of Sumi’s past, where she stillness had been ‘thrust upon her.’ However, I’d like to focus on Sumi’s murder. There’s a reason Nancy is the point of view for this, and part of that is to focus on the true tragedy of Sumi’s death. Nancy doesn’t see death itself as a bad thing. She’s lived in the Halls of the Dead, she’s met dead people, so for her death is barely an inconvenience. However, death means that Sumi’s story — this part of it — is over. Someone ended Sumi’s story, and that’s not right. We’ve been presented with many examples of people trying to control the narrative of others, but this is the extreme example. Here, it is not presented as control, but rather as theft:

“Someone had stolen that from her. Someone had stolen everything from her.”

Mystery and Plot

“There was no way she could have washed the blood away so completely in one of their shared bathrooms, not without being seen. Even in the middle of the night, the amount of scrubbing required to get the blood from under her fingernails would have attracted attention, and she would have been undone.”

We get the first half of a clue here: we’ve narrowed the suspects to those who have private bathrooms. Now we don’t know for sure who those people are, and there are probably a few of them, but we will get a mention of private bathrooms in the next chapter. Pretty ingenious hint.

It’s worth noting that this is the first chapter of Part 2: With Your Looking Glass Eyes. This is the part where the ‘plot’ properly starts, where the murder mystery comes into play. It doesn’t mean that what came before was just a prelude, but it indicates a change. From here, the focus will be less on Nancy’s discovery of the school, and her struggle with her own story, and more to do with the troubles of the school.