After three volumes heavily focused on the awakened sleepers just trying to survive in their nightmarish thorn-and-monster-strewn environment, the story settles down for a while and spills its guts. Many of the things that have heretofore gone unexplained see extensive clarification in this volume, most notably what, exactly, the Medusa “virus” really is and how it is directly connected to the disastrous events which created the current environment. The mechanics laid out here offer some intriguing twists on sci fi and horror gimmicks and, to an extent, explain the mysterious little girl who has been hanging around since the beginning. They also imply that the title of the series most likely refers to the newly-introduced character Zeus. During that time we also get a more detailed background on Marco which decisively lays out exactly who he is, what he's doing here, and (more or less) what his real goals are.

The other big secret to be dealt with is, of course, the security videotape which first popped up in volume 2. At the time other characters commented that Kasumi needed to see it, and by the end of this volume readers will finally understand why. Though the ultimate revelation is shocking and raises oodles of fresh questions, it should not be entirely unexpected given the way the storytelling has set things up so far. It certainly casts many previous events in a new light, especially given what the survivors learn about Medusa, the actions of Zeus, and the misconceptions Marco probably had about the content of the video. Annoyingly, the whole videotape business gets spread out over five chapters while decidedly less interesting events and flashbacks progress. Sure, Marco's backstory is critical to a full understanding of what has transpired, but did it really need to be so long?

Despite all the revelations, the series does not forget its horror/thriller foundations, although those elements have less prominence here than in previous volumes. Certain characters still get their fair share of action, a convincing threat factor ratchets up the tension when needed, and the opposition includes monsters aplenty. Zeus seems a little too much like a stereotypical whacko mastermind, but at least his appearance finally gives the story a true villain.

The somewhat rough look of the artistry suits the content well, although it also results in character designs that look somewhat like cartoonish variations on more typical manga designs. Manga-ka Yuji Iwahara's artistry looks its best when detailing monsters or showing off the colored opening pages; moreso than most manga, this one could have benefited greatly from being done all in color. He shows a good sense for staging action content and portraying horrified reactions, but struggles more with other expressions.

Tokyopop's release of this volume leaves the original sound effects intact without translation, which can sometimes cause minor issues with fully understanding a scene. It includes a one-page story review at the beginning, a brief Next Volume preview at the end, and a two bonus pages in between but after the main story. At 235 pages it clocks in a bit longer than your typical manga volume but never seems quite that long, nor does it have any increased price.

Numerous major revelations about the Medusa “virus” and apocalyptic circumstances, amongst other shocking secrets, come out in a volume which balances action, horror, and tedium with lots of cool story developments. It offers plenty to like in further establishing this as a solid horror/thriller series.