I don’t have a verified ending for *Nineteen Quiet Rooms* by Ottilie Marsh, and I don’t want to make up a twist that could be wrong before your book club.

If you need to bluff tomorrow: skim the **last 15–20 pages**. Look for:
- who is actually narrating / whose voice changes,
- what the “nineteenth room” turns out to be,
- any repeated name/object that suddenly makes sense.

If you paste the final chapter or even the last few pages here, I can summarize it and tell you the twist cleanly in a couple minutes.

Safe non-spoiler bluff: “I thought the ending really recontextualized the narrator—it made me reread the whole book as more about isolation and unreliable memory than about the house itself. What did you all think of the final reveal?” Then let other people talk.