UPDATED REVIEW (Original Review below)Since my first review, I bought another three copies to give as gifts to different groups of friends. One of those three books had the printing problem that some other reviewers have identified. The opening puzzle does use images with several levels of darkness - some are very light. However, four or five pages of one of the three books had pictures so light that my friends couldn't make out the image. (It'll be obvious if you're missing an entire image based on the instructions of the puzzle.)I ordered a replacement, which arrived without any printing issues, so we swapped out the bad pages and sent them back with the bad book. It's sad to see poor reviews due to a printing issue and people giving up after such an experience. I can't say I wouldn't do the same. But having completed it, and seeing the fun that my friends are having, the book still deserves a 5-Star rating despite one book having printing issues.Original Review:Amazing. I am blown away by the amount of fun packed into this book. The further I got into the book, the more appreciation I had for the meticulous planning that went into it. I highly recommend it and I plan to order a couple more for friends.At the start, I cringed as I contemplated tearing out that first page, trying to justify leaving it in the book. (It's not like the author would know!) But, the book has one immutable rule: Follow Instructions. Oh, the agony! With a guilty heart (and a look of absolute horror from my 6yo niece that could only be interpreted as "Everything you have ever taught me is a LIE!"), I held my breath, and tore.Over the subsequent hours and days, liberated pages flew about the room in a frenzy of tape, scissors, shoes, and ducks. Finally, our exhilarated team emerged victorious! We felt as if we had conquered an "Escape the Room" event, without ever leaving the house.Things I LOVE about this book:-It's accessible. Don't be intimidated. I'm not sure how he (the author) does it, but all the puzzles were very challenging, while never feeling overwhelming.-It's original. These puzzles are fresh. Even those that look traditional have an extra something that makes them stand out. (I wish I could tell more but I don't want to spoil anything!)-It's suspenseful! Our group's collective thought process: Stage 1: "Wait, what are we supposed to do?" Stage 2: "He (the author) can't POSSIBLY want us to do X" Stage 3: "I can't believe we're doing X. There's no way this is going to work" Stage 4: "We definitely messed something up. Let's go back." Stage 5: "Wait, there it is!" And you realize, everything you were looking for was right there with you all along. (This cycle repeats itself many times.)Advice:I wish that I had tracked our time better, but with a team of three, we completed it in about 5, 4-hour sessions. If I could do it over again, I would have gathered more people and tried to knock it out in a single day.