It faithfully adapts the game and has some new information that weren't explicitly stated in the game. We get to see what was on the characters mind, which is a nice addition, particularly the Adam and Eve side stories in their point of view in each chapter. If you want to relive the experience of playing the game, you might want to get this book, though this isn't a must have. The other book (Short Story Long) covers around 100 pages about A2 and the resistance. You might want to get that one.