As Fog battleships Haruna and Kirishima begin their attack on Yokosuka, we begin to learn a little more about their different personalities…
While Haruna is more thoughtful and reserved, preferring to study and catalogue human words; Kirishima is haughty and aggressive, believing that the superiority of the Fog in terms of firepower and tactics (with the introduction of mental models) can easily crush humanity’s resistance.
As Kirishima makes short work of the limited defences on the human side, the I-401 goes on the offensive. Gunzou decides to keep their “home court” advantage and draws both Fog battleships deeper into the harbour while hiding in the sunken ruins of Old Yokosuka city.
Haruna and Kirishima contact Iona and ask her to reveal her reasons for joining the human “side”. Iona explains that she herself doesn’t know the reasons, but she understands that she needs a captain and that she is now Gunzou Chihaya’s ship.
Gunzou sets up numerous automated torpedo launchers, which he uses to attack both Kirishima and Haruna while masking his true location. His diversion is unsuccessful though and his last attack reveals his position to the two Fog ships. Kirishima, who begins to feel a little agitated, launches a huge barrage of torpedoes at the I-401.
Taking advantage of the numerous explosions, the I-401 pretends to have been hit and sinks down to the ocean floor.

Automated torpedo launchers
Haruna and Kirishima correctly deduces that the I-401 has survived and both ships decide to merge their supergravity cannons together and eliminate the I-401 once and for all.
This proves to be their downfall — it is revealed that for the supergravity cannon to be able to fire, there has to be an opening in the ships’ Klein Field. Gunzou successfully slips his last corrosive torpedo into the opening and the blast deals a fatal blow to both ships, who are then destroyed by a final torpedo barrage from the I-401.
Just before Kirishima’s mental model is destroyed in the blast, Haruna’s mental model retrieves Kirishima’s core. Haruna is eventually found (in a state of undress — fanservice for Haruna fans) by the loli little girl introduced in the previous episode.
Fanservice moment aside, it was a real action-packed episode of Arpeggio of Blue Steel — lots of explosions, tension, battle tactics and more explosions (could have been a Michael Bay movie…). While I was a little disappointed that they cut out quite a number of characters (and a submarine) from the anime, it has worked out quite well so far. I am still hopeful that the “missing” characters might eventually be introduced at a later stage.
If you haven’t already guessed, the “little girl” is obviously a lot cleverer than she seems to be (correctly identifying the sand as nanomaterial). If you do want to find out her identity and the role she plays in the series, then keep a look out for the next episode review!