X Marks the Spot
A branching book series by Brian Thomas
In these books, you decide where the story goes.
The decision is yours. That's why it's Decidable.
X Marks the Spot is a series of books where you choose the path. Every choice sends you somewhere new, and only the right ones lead to the treasure.
Begin at §1. Never read straight through.
Coming soon from Brian Thomas.
Why Decidable?
Most books go one way, from the first page to the last. These books don't. You pick where to go next, and your choices change the story.
These books are decidable by the reader. That's the whole point, and that's why the site is called Decidable.
How a branching book works
- You are Lennie Bell. The story is told to you, and you decide where it goes next.
- Remember the clues. Some paths only open for readers who noticed a detail earlier in the book.
- Every book is one adventure. A new place, a new puzzle, the same traveler.
- Easy and Hard editions. Pick the level that suits the reader.
On the shelf
Book 1The Square KeyEasy · Hard 
Book 2The Mountain PassEasy · Hard 
Book 3The Hidden TunnelEasy · Hard 
Book 4The Sharkwater BellEasy · Hard 
Book 5The Nameless WellHard 
Book 6The Silent FlightHard 
Book 7The Rainforest CipherHard 
Book 8The Midnight TableHard