Yet another I Spy game, but as far as I know this one is not based on any previous existing I Spy game. I Spy Ultimate is one of the I Spy books, but as far as I remember has nothing to do with the game outside of name and brand. This one was also enjoyable and was conceptually interesting, but I did not like it as much as the others. It may be 'cos I really like having a theme that each game follows, and Ultimate I Spy doesn't really have one. It's good either way.