3.5 stars
You are a police investigator trying to catch a corrupt cop within your organization and you have to solve 99 puzzles along the way before coming to the 100th big question of “who do you think is the traitor?” Some puzzles are very easy, some are challenging. Some require (not-so) general knowledge in order for you to be able to solve them.
Although I felt frustrated with my lack of technical knowledge and patience to play the games on paper (sudoku and nonogram are way easier on apps where you don’t have to pen everything down yourself), I found the book overall quite fun. I liked the ending as well.