Codex Silenda is a five page book that features five intricate puzzles. Each page features a unique puzzle that requires the user/reader to unlock the corresponding bolts in order to progress to the next page.
As the puzzler moves through the book, a story begins to unfold, depicting the story of an apprentice in Da Vinci's Workshop who encounters the same Codex. However in the story the Codex acts as a trap set by Da Vinci to capture any would be spies/snoopy apprentices in order to protect his work. The only way to escape is to solve each of the puzzles before the master returns from his trip.