Four hours into the Battle of the Indian Ocean, the Nadesico continues to sit idly by one hundred kilometers behind the front lines as the sole member of the 103rd Rear Support Group. To pass the time, Yurika sings Nadesico‘s opening theme song while the rest of the crew amuse themselves with various games. Erina tries to give a stirring speech about how the Jovian Lizards will soon be driven off the Earth, and then the Nadesico will lead the invasion of Mars. Ruri interrupts her with a report of boson activity in the rear hanger. Suddenly, an explosion rips through that area, and Ruri reports that a new battleship has emerged from a Chulip some distance behind them and is headed their way. Another boson reading is reported at the forward tip of the Y unit, which also suffers from an internal explosion. Fortunately, the damage is somewhat contained by Uribatake’s distortion field blocks, but the damage is still significant. With the battleship rapidly approaching, Yurika decides to run and orders Minato to take the Nadesico into orbit. Doing so narrowly prevents the bridge from being destroyed by yet another explosion. As they make their way into orbit with the Jovian battleship right on their tail, Inez explains that the enemy seems to be using their new Chulip-less boson jumping ability to teleport warheads inside the ship, bypassing their defenses–a ‘boson cannon’ if you will. Judging by the fact that they’re all still alive, Inez believes that the boson cannon has a limited range–probably around 100 kilometers, judging by their first and second shot. With no way to get the Aestivalises close enough before being destroyed and the gravity blast cannon useless against another distortion field, the crew is at a loss as to what they can do. On the enemy ship, the young executive officer mocks the crew of the Nadesico as cowards for running away, but is reprimanded by the captain who notes that running prevented them from being destroyed by their third shot. He decides that the enemy captain deserves respect for that, and orders that his mech Denjin be kept ready to launch, just in case. As the crew mulls over their predicament, Akito regrets that they had to leave the ocean, as Howmei was going to teach him how to fish after the battle. He was looking forward to fishing because Mars didn’t have any fish. Yurika hears him talking and suddenly knows exactly what they need to do. On Yurika’s orders, all missiles are set to timed detonation and the Aestivalis pilots prepare to move out. With preparations complete, Yurika orders the phase transition engines powered down along with all non-essential electrical systems. Without the phase transition engines, they’re defenseless, but the enemy will be unable to track them. Erina asks Yurika if she really thinks this is going to work, to which Yurika replies that she has faith in her enemy–they are, after all, human beings.
On the enemy ship, the executive officer is shocked when the Nadesico suddenly drops off all their sensors. Despite the fact that the Nadesico is now defenseless, the enemy captain recognizes that the current situation is not at all in their favor–they can’t see the Nadesico, but the Nadesico can easily see them, even with passive sensors thanks to the amount of energy output by a typical battleship. He orders his ship to be brought to a relative stop so they can observe the situation a bit longer. Meanwhile, the Nadesico ejects ballast normally used for underwater operation in order to maneuver without the engines. Yurika orders the Aestivalises to perform manual launches by running out of the launch bay under their own power. After they clear the ship, they deploy their solar sails as Yurika assures Akito that this plan will work, once again pointing out that they’re fighting fellow humans. Suddenly, the enemy ship fires its gravity blast cannon at the Nadesico‘s last known coordinates. When nothing explodes, they are assured that the Nadesico is maneuvering somehow. Knowing that the Nadesico lacks the firepower for a surprise attack, the enemy captain wonders what their next move will be. Shortly after the blast, Yurika orders all the missiles dropped in the direction of the enemy’s path. Mr. Prospector complains that missiles are expensive, but Yurika assures him that you need a lot of bait to land a fish. Erina angrily tells her that they are not fighting fish, but Yurika responds that they are fighting humans, and humans can always be counted upon to think and react accordingly. With that, she orders Minato to return the Nadesico to its original position. When the enemy ship comes within range of the missile field, several of them activate and impact on its distortion field, surprising the enemy. Hoary suggests that they should fire the gravity blast cannon now, detonating all the rest of the missiles, but Inez reminds him that that would be useless against their distortion field. Yurika smiles tells them that fishing is all about patience. As their distortion field is pounded by missiles, the young officer demands that they trace the missiles back to their point of origin. When informed that no single point of origin can be established, he orders that a probable enemy location be calculated from the dispersion of missiles and orders the ship to change course toward that location. The captain countermands that last order, informing his subordinate that they would be walking into a trap–there’s no way the enemy would still be in that location. Instead he orders the current heading to be maintained. On the Nadesico, Mr. Prospector reports that the plan to lure them into the missile field has failed and suggests that they turn on their distortion field now. Yurika is remains unperturbed and disregards his suggestion, telling him that the Aestivalises can handle the rest. The enemy ship finally comes within range of the dispersed Aestivalis team, which detaches from their solar sails and plow in at full combat speed. Hearing this, Yurika orders the phase transition engines back online and the energy feeds to the Aestivalises is reestablished. Finding themselves surrounded, the enemy captain realizes too late that the missiles were just a faint to lure them within range of their humanoid fighters. He orders all unmanned units launched. Erina sourly notes that for a person who doesn’t want to fight other humans, Yurika is quite good at it. Yurika responds that she will not allow the Nadesico to lose a battle until this war is done–after all, the Nadesico is the only place Akito has to come home to. The Aestivalises make their way through the enemy fighters to the battleship’s distortion field and use Uribatake’s new distortion field-penetrating lances to punch through. The enemy captain orders the boson cannon to fire on the Nadesico, but the increase in boson readings lead Akito right to the cannon. In an attempt to defend the cannon, the young officer launches in the Denjin, but is too late–Akito takes out the cannon with time to spare. While Ryoko, Izumi, and Hikaru draw the Denjin’s attention, Akatsuki sneaks up behind it and manages to deliver an unexpectedly fatal blow. As the Denjin begins to overload, the executive officer heroically boson jumps away from the ship to spare it from harm. To the captain’s relief, however, he manages to eject before the Denjin explodes. Noting at what a handful his executive officer is, the enemy captain orders his ship to lay down a covering fire and withdraw to rescue him. Noting their withdraw, Yurika orders a course back to Earth be plotted and executed as soon as the Aestivalises are recovered. Megumi announces that they have received a dispatch from the enemy captain which reads; “I pay my respects to the bold and courageous leadership of your vessel. I am taken aback to learn a dashing man of action such as yourself is in the dastardly United Earth Federation. We shall lock horns on the field of battle again sometime. Captain of the Kannazuki, Genpachiro Akiyama.” Needless to say, Yurika is far from pleased at being referred to as ‘a dashing man of action.’
Obviously, this episode borrows quite a bit from old World War II submarine movies, what with the whole silent running aspect and the fact that it shares the title with a famous submarine movie from the 50s. Despite it being pretty much entirely filler, it’s fairly clever and enjoyable episode. Despite supposedly being a strategic genius, Yurika never really needed to be all that strategic when her ship could simply overpower anything the Jovians could throw at it. And even when they do get out gunned, it’s usually Akito and the Aestivalises who save the day. So it’s nice to see her getting the chance to save the day for once.