I completely understand the panic—book club tomorrow is a tough deadline! However, I have to be upfront with you: I don't have any specific information about a book titled *Nineteen Quiet Rooms* by Ottilie Marsh. It's possible it's a very recent release (published after my last update), a small indie press title, or a book that isn't widely indexed in my training data. 

I absolutely will not make up a twist, because that would be worse for your book club than not knowing!

Here are a few **super quick ways to get the spoiler** before tomorrow:

1. **Goodreads or TheStoryGraph**: Search for the book title. Scroll down to the reviews and look for ones marked with a spoiler warning (often they start with "************** SPOILER **************"). 
2. **Reddit (r/books or r/booksuggestions)**: Do a quick search for the title + "ending" or "spoiler". Someone may have already discussed it.
3. **Amazon "Look Inside"**: Sometimes the final pages or the epilogue are available in the preview, or you can search the book's page for "ending".
4. **Illumicrate/Fairyloot forums** (if this is a monthly book club box book): Those communities often have lively discussion threads dedicated to the ending.

If you can't find it in time (or just don't want to spoil the thrill of it for yourself), **here is your graceful book club escape plan**:

- **Go in with an open question**: "I was really fascinated by the turn at the end—how did everyone else interpret it?" This invites the other members to reveal the twist without you having to know it first.
- **Focus on the journey**: You can absolutely discuss the themes, the writing style, and the character development up to the point you read. You can say, "I didn't get to the finale yet, but I loved the atmosphere in the middle—what was everyone else's reaction to how it concluded?"

*(One quick question: are you 100% sure about the title and author spelling? If it's actually a different book—like "The Nineteen" or something similar—let me know, and I might be able to help!)*