Original Edition Cover · Instant Digital Delivery
The Twenty-Fourth Door
A Christmas Escape Room Advent Calendar Puzzle Book for Adults
By Filip S. · First Digital Edition (2026) · English
- Included Files
- PDF — fixed-layout digital edition
- Length
- 108 PDF pages · 12 Sections
- Est. Time
- ~3.0 hrs structured work
PDF — fixed-layout digital edition. No physical book included.
Twenty-four days. Twenty-four locks. One stolen star.
It is the first of December, and somebody inside this building means to steal the Marchmont Star.
You are the new night security officer at a seven-floor department store: two hundred and eleven keys, a boiler older than anyone still working there, and a Christmas Eve ceremony at five o'clock when a glass-and-silver ornament made in 1888 comes out of the strongroom and goes up on the tree.
It is not going to get there. You have twenty-four days to work out who , how and when — and everything you need is printed inside.
Open one day at a time. Each day gives you what happened, the piece of paper it turns on, and one puzzle. Every puzzle answer is a number. Take it to the Key Board at the back and read that entry: if you were right, the case moves on. If you were wrong, the drawer is empty and you go back and work it again.
What You Will Put in Place
Concrete scripts, tools, and steps inside The Twenty-Fourth Door:
- One unbroken mystery across twenty-four days — not twenty-four unrelated brain teasers
- Ciphers, logic grids, timetables, floor plans, sequences and pre-decimal money
- Twenty-four drawn exhibits: the store in section, the pneumatic tubes, the ledger, the rota, the staircase, the insurance photograph
- Three hints for every puzzle — a nudge, a method, and the answer — shuffled with an index so your eye cannot catch the next one
- A full solution, and seven rules of fair play printed before the first of December and kept
Written Specifically For
- →Adults who love fair-play logic puzzles, mystery casefiles, spatial challenges, and escape-room books
- →Gift buyers looking for an instant printable activity book for parents, partners, holiday evenings, or travel
- →iPad / tablet stylus users and pen-and-paper solvers who want crisp, full-page printable layouts
Door #01: The Night Watchman's Key Rack
Three brass keys hang beside the strongroom ledger: #14, #27, and #42. The night log states: 'Do not use the even-numbered keys, and add the digits of the remaining key to find your Key Board drawer.'
- • Eliminate any key whose number is divisible by 2.
- • Sum the two digits of the single odd-numbered key.
Clear Scope Before You Spend a Dollar
What This Book IS
A fair-play, screen-free collection of original puzzles, drawn exhibits, tiered hints, and structured daily or episodic sessions—delivered as a high-resolution Printable PDF + Tablet Stylus edition.
What This Book Is NOT
Not a medical treatment and never marketed with exaggerated claims of 'raising IQ' or preventing neurological disease.
Designed for enjoyment, structured mental engagement, and screen-free routine — not medical advice or clinical cognitive therapy.
Structure & Chapters
- 01DAY 1 · MONDAY 1 DECEMBER
- 02DAY 2 · TUESDAY 2 DECEMBER
- 03DAY 3 · WEDNESDAY 3 DECEMBER
- 04DAY 4 · THURSDAY 4 DECEMBER
- 05DAY 5 · FRIDAY 5 DECEMBER
- 06DAY 6 · SATURDAY 6 DECEMBER
- 07DAY 7 · SUNDAY 7 DECEMBER
- 08DAY 8 · MONDAY 8 DECEMBER
- 09DAY 9 · TUESDAY 9 DECEMBER
- 10DAY 10 · WEDNESDAY 10 DECEMBER
- 11DAY 11 · THURSDAY 11 DECEMBER
- 12DAY 12 · FRIDAY 12 DECEMBER
DAY 1 · MONDAY 1 DECEMBER
This is a work of fiction. Halbury, Cathedral Row, Marchmont & Sons and every person in this book are invented. Any resemblance to real persons, living or dead, or to real places or businesses, is coincidental.
No part of this book may be reproduced or transmitted in any form without the prior written permission of the author, except for brief quotations in a review.
Open one day at a time, from the first of December to the twenty-fourth. Each day has three parts: what happened, the piece of paper it turns on, and the puzzle.
Want comfortable dark/sepia font controls or the full 108-page edition? Use Look Inside — Read Free Sample above or check the formats listed for this title before purchase.
The Complete Escape Room & Detective Mystery Collection
Five complete solve-it-yourself mystery books—including The Twenty-Fourth Door holiday advent mystery, The Clockmaker's Last Hour, The Black Clock Files, The Island of Seven Bells, and The Thirteenth Carriage.
Complete 5-Book Digital Pack
Just $13.20 per complete ebook
Frequently Asked Questions
What digital formats do I receive immediately when I buy The Twenty-Fourth Door?+
This title is supplied as PDF. Check the reading guide for compatible software. No physical book or e-reader is included.
Who is The Twenty-Fourth Door written for—and do I need technical or specialist background?+
The Twenty-Fourth Door is written in plain, direct English for busy readers solving a specific problem. Every term, script, or step is explained on the page without filler or assumed insider jargon.
Can I read this ebook on my Kindle, iPad, iPhone, or Android phone?+
This title is supplied as PDF. Check the reading guide for compatible software. No physical book or e-reader is included.
How is Filip S.'s approach different from generic AI or self-help books?+
Every book follows one editorial rule: 'A plan, not a promise.' Instead of motivational padding or unverified claims, you get concrete scripts, checklists, decision trees, and honest scope boundaries.
Can I save money if I want multiple books in this topic lane?+
Yes. Every single-book page includes a one-tap Digital Bundle upgrade that pairs related titles in the same category at up to 35% off individual ebook prices.
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