* * * * *
The Order 66 arc (Season 6, Episodes 1-4) builds upon what made the Clone Troopers such fascinating characters in the series, but unfortunately it also undermines that in an important way. As suggested by the title, this arc is intended to serve as an explanation for Order 66, for why the Clone Troopers suddenly turned on their Jedi compatriots after receiving an order from Emperor Palpatine. In short, the clones were programmed with a sort of tumor. As an explanation, I find it extremely unsatisfying. However, the second half of the arc focuses on Clone Trooper Fives and his reaction to the discovery. It's a great character moment and raises some great questions about the nature of individuality amongst the clones.