This review includes slight spoilers.
Review:
Black Butler: Book of Circus could, I suppose, be considered the third season of the Black Butler anime. However, I think it's a good thing it wasn't called that anywhere on this boxed set, because that isn't quite correct. Calling it a reboot isn't entirely accurate either.
Those who have only seen the anime and haven’t read the manga might be a bit confused by the anime timeline. Book of Circus does something very similar to what Fullmetal Alchemist: Brotherhood did, rebooting the series in order to follow the manga more closely, but instead of starting from the beginning it starts from the point in Season 1 where things went in their own direction. The arc involving Ciel’s aunt was true (and gets a few references in Book of Circus), but beyond that the slate was wiped clean. The very shaky Season 2 might as well not exist. For those wondering which volumes of the manga Book of Circus covers, it’s volumes 6 to 8.
In Book of Circus, Ciel is charged with looking into the mysterious disappearances of several children. The Queen believes they’re tied to a certain circus that’s always in the area at the same time as the disappearances, so Ciel and Sebastian check it out. They end up joining the circus to get a view of things from the inside. The things they uncover are shocking and horrible, and turn out to be more connected to Ciel than either of them originally anticipated.
