I have to admit, I was expecting a lot more of this episode to focus on the rest of the cast’s effort to rescue the now-submerged Iona and Gunzou. I wasn’t expecting, or even really hoping for, a focus on those two. But that’s the direction the show decided to go in, and it produced an outstanding piece of work as a result. There were a few moments where they went a little overboard with the drama (Takao’s sacrifice laid it on pretty thick), but the majority of this episode was quietly stuffed with character detail for Iona and Gunzou.
One thing that really stood out to me in this episode was the lack of noise all throughout the entire time Gunzou and Iona were trapped on the ocean floor. The merits of prolonged silence/lack of music as a scene design choice are many. It’s a really, really powerful tool, and it shows the staff trust their characters-slash-material-technique enough to stand out without what’s normally one of the key aspects of presentation. The better your OST is, the more guts it takes to ditch it.* This was, in hindsight, the perfect choice for the very isolated and quietly urgent atmosphere of that scene.
That sound direction by an uncredited staff member isn’t the only impressive technical part of this episode. There was also return on an investment Kishi Seiji had been making for weeks; Iona’s initially robotic motions and expressions have become much more human. One of the central points of the episode was that Iona had evolved as a character enough to prioritize Gunzou’s life over the fulfillment of the nominal #1 objective. To that end, it helped a lot that she was showing very real, if subtle concern on her face while she was finding out that cold temperatures are bad for humans.
I’m not entirely clear on where the show stand for the ending at this point. It would be anticlimactic if the crew just managed to successfully deliver the warhead, especially with so many loose threads (Kongou, the creepy twins, and the long-term outcome of the conflict) still out there. It feels likely we’ll wind up with another naval battle and successful completion of the mission at hand to close out the show, with a possible sequel hook mixed in.**
*Somewhat related tangent; it’s been a while since I’ve seen Figure 17. That series is notable in quite a few ways; it was one of the first series to adopt the one hour, once per month format later used by Katanagatari. Another way was that it pulled a version of what Arpeggio just did, putting in something on the order of 20 minutes of straight silence to honor a somber time in the lead female’s life. Which had the unintentional side effect of making it perfectly clear just how weak the series’ default soundtrack was.
**Not at all out of the question, given the fact that the amazon special edition of the show’s first volume sold out about 20 days before the release after getting something in the range of 4000 preorders. With another 1000 apiece for the regular BD (preorders have skyrocketed after the limited one cashed out) and the DVDs, the sequel probability equation predicts a 44% chance for a sequel if the show gets no license, produces no notable increase in manga sales***, and goes on sale today without getting 15 extra days of preorders.
***It quite possibly did cause an increase in manga sales; volume 7 didn’t chart in the May when the threshold was 19000 volumes, and volume 8 sold 33000 volumes at the end of October. That might be lowballing gains on that side, as I’ve found in the 2011 and 2012 data that gains in sales from volumes released less than two months after the anime airs are usually dwarfed by subsequent totals.