Spoiler Warning! If you aren't up to date with the events of the previous volume, you risk learning something here you won't want to. Seriously, read volume 20 before you read this review of 21.

The final volume in Higurashi: When They Cry's penultimate arc is both one of the most satisfying and the most disturbing books in the series to date. Answering the earlier Curse Killing question arc, the Massacre Arc not only showed us what Rika has been going through for the last century, but it also revealed who was behind at least one of the cursed years. The answer was one that is both obvious and shocking, given the character's behavior across the other arcs, most specifically the Eye Opening, and with this last volume of the arc, we finally get inside the villain's head. While the answer arcs have taken a more open approach to narration than the question arcs did, we have strictly remained within the minds of the good guys, so this is the first time we see what the other side is thinking. The result is chilling.

The book opens with Takano's narration as she details her side of the story. She has been a shady character almost from the get-go, but now we see just how deranged she really is. Hinase Momoyama's art, which up to this point has been pleasing but lacking in the visceral power of other series illustrators, truly comes to the fore with her depictions of Takano's increasing madness, slightly distorting the woman's face more and more with each image of her, so that she starts the book looking like a serpentess and ends being almost fully inhuman as the emotions take over her physical appearance. It also turns out that Momoyama's art style is better suited to moments of shocking, realistic violence rather than drawn out spatterfests – the violent deaths in the is volume are much more visceral and frightening than those in previous books, with perhaps the exception of the nail-pulling scene in the Eye Opening arc. Less is absolutely more in this case, and the briefer, less bloody deaths have much more impact than those that are more drawn out.

On that note, this is by far the most disturbing volume in the series to date. Sensitive readers need to be aware that the violence is more realistic this time, bringing things closer to home. Events in the end of the book have very clear Holocaust themes, and those of us who grew up on tales of lost relatives will find it particularly difficult reading. Even if that is not in your family history, the use of certain characters, the methodology employed by the villains, and scenes of the aftermath are very upsetting, especially when we put the pieces together from previous arcs.

That, however, is one of the ways that the Massacre arc's final volume really succeeds. It pulls together bits and pieces from all of the previous books, answering questions and clarifying plot points in a way that makes you wonder why you never saw it before. Ryukishi07 has outdone himself here, and the fact that he still managed to withhold some information in order to get a final arc out of the series, the so-called “good end,” is also worth mentioning. We finish the book only partly content – yes, we know who did it and why, but there are still just enough missing pieces of the puzzle to niggle at the mind. This book is satisfying, but it is also one that leaves you begging for the final answers.

Given that series volume 20 was somewhat less than engaging for most of the book, this is an impressive feat. With the opening of volume 21, the gathering storm explodes upon the town of Hinamizawa, making us wonder if maybe those people who wanted to build the dam weren't right after all. The tension remains high throughout, and if Ryukishi07 harps a bit on the power of friendship, it doesn't detract from the unfolding horror. The very real chance that good might succeed also works to keep the energy of the volume tense and high, making the ending (before the Holocause scenes) convey a sense of determination rather than disappointment.

Higurashi: When They Cry is one of the most effective horror manga on the market at the moment, and this volume is no exception. Mixing psychological, biological, and violent warfares together with a dose of the supernatural and a little old fashioned friendship, the conclusion to the Massacre arc is one that will stick with you even as you wait impatiently for the final arc. Despite its high page count, this is a one-sitting book, and if you end it feeling both relieved and disturbed, then it has done its job. The horror comes, after all, from knowing that it could have been avoided...and now we know how that can be done.