The Third Battle of Tiamat continues. The 11th Fleet under Willem Holland dominates the battlefield for a few hours with its wild "pioneer-like" tactics. However, just as it reaches its limit of expansion, Reinhard von Müsel orders his fleet to conduct a long range pinpoint attack against the heart of the 11th Fleet and succeeds in destroying a significant number of ships, including Holland's flagship Epimetheus. With the loss of its commander, the 11th Fleet is quickly routed by the other Imperial fleets. Further damage is minimised though with the timely intervention of the 5th Fleet and 10th Fleet, who cover the retreat of the surviving ships from the 11th Fleet before withdrawing completely from Tiamat Starzone. For his efforts in the Third Battle of Tiamat, Reinhard is promoted to the rank of Admiral and is granted a couple of honorary positions. However, none of these positions delights Reinhard more than the bestowal of a personal flagship, the experimental battleship Brünhild, to him.

In December 794 UC, to commemorate the thirtieth year of the reign of Kaiser Friedrich IV, the Galactic Empire announces a large scale military campaign against the Free Planets Alliance comprising of 35,400 ships. While news of the impending invasion quickly reaches the Alliance via Fezzan, the Alliance response almost causes a scandal when a merchant convoy bringing vital supplies to the front lines is almost destroyed by Imperial cruisers due to the majority of the Alliance escorting warships shirking their responsibilities and abandoning the merchant ships before they reach their destination. By February 795 UC, the Alliance decides to intercept the Imperial expeditionary force in Tiamat Starzone with the 5th Fleet, 10th Fleet and 11th Fleet, with the possibility of the 4th Fleet and 6th Fleet being added as reserves. When both sides finally clash with each other later in the month, the 11th Fleet under Willem Holland leads the opening phase by ignoring standard tactics and charging into the Imperial line in a haphazard fashion, which manages to confuse the Imperial forces.

Margareta von Herxheimer accepts the deal proposed by Siegfried Kircheis, in which she will reveal the access code for the directional Seffle particle generator prototype in exchange for her freedom to defect to the Free Planets Alliance along with all the assets of her family. Lieutenant Commander Bendling, an officer dispatched by Imperial Military Intelligence to oversee the entire secret mission, unlocks the prototype in the presence of Reinhard von Müsel and Kircheis. The prototype not only contains the program that enables directional Seffle particles, but also disturbing information about the circumstances that caused the defection of Count Herxheimer. Shaken by those contents, Bendling decides to volunteer as the guardian for Margareta and to accompany her defection, essentially deserting his post. Approved by Reinhard and accepted by Margareta, he then accompany Margareta and leaves for the Alliance in Herxheimer's ship after the prototype is successfully transferred to the Hässliche Entlein. A few days later, the Hässliche Entlein reaches the vicinity of Iserlohn Corridor and is met by a waiting Alliance blockade. Low on fuel and supplies after their long voyage, Reinhard decides to take an immense risk by using the prototype, whose directionality program is not perfected yet, to saturate the blockade with Seffle particles and ignite them. It succeeds and Reinhard is able to lead the Hässliche Entlein unscathed into the Iserlohn Corridor, where it receives a resupply organised by Ernst von Eisenach before returning to Iserlohn Fortress safely and completes its mission.

The Hässliche Entlein manages to evade and destroy the pursuing Alliance patrol squadron through a timely usage of the captured directional Seffle particle generator prototype. However, with the prototype locked digitally within Count Herxheimer's ship, the crew of the Hässliche Entlein are neither able to access the program that grants the Seffle particles directionality, nor are they able to physically move the prototype to the Hässliche Entlein. As the Hässliche Entlein makes its way back to the Iserlohn Corridor via a different navigation route to avoid possible Alliance detection, Siegfried Kircheis proposes to Reinhard von Müsel to strike a deal with the Count's ten year old daughter Margareta von Herxheimer, who is the only survivor of her family and the only person left who knows the access code to unlock the prototype.

The cruiser Hässliche Entlein successfully infiltrates Free Planets Alliance space from the Iserlohn Corridor undetected. After an uneventful journey to the exit of the Fezzan Corridor, the Hässliche Entlein finally catches up with Count Herxheimer's ship. Reinhard von Müsel orders a swift attack to disable Herxheimer's ship and destroy its escort while Siegfried Kircheis leads a boarding party into Herxheimer's ship. The directional Seffle particle generator prototype is located and secured; however, the entire Herxheimer family has died, except for the Count's daughter, due to a decompression accident while trying to escape. Reinhard then orders the Hässliche Entlein and Herxheimer's ship to retreat and evade an incoming Alliance patrol squadron that is alerted by the destruction of Herxheimer's escort ship.

In December 792 UC, after receiving the appointment of captain of the cruiser Hässliche Entlein for six months following his accolades from the Fifth Battle of Iserlohn, Reinhard von Müsel is tasked by Imperial Military Intelligence to track down and apprehend Count Herxheimer, who has fallen out of favour and is trying to defect to the Free Planets Alliance via Fezzan. Herxheimer, prior to his defection, had stolen a directional Seffle particle generator prototype. Reinhard is also ordered to retrieve that prototype, lest it falls to Alliance hands. However, since the details of Herxheimer's defection are confidential, Reinhard has to execute the mission with only the Hässliche Entlein inside largely unknown Alliance space and has to expect no overt support from the front lines.

Being pressured by Sussanna von Beenemünde and wanting to uphold his pride, the assassin who previously duelled with Reinhard von Müsel challenges him again to another duel. Reinhard, feeling equally dissatisfied with the outcome of the previous duel, accepts the challenge. Through his accurate reading of the assassin's situation and with some help provided by Siegfried Kircheis beforehand, Reinhard is able to defeat his much more skilled opponent. The assassin, unable to get over his defeat, commits suicide. Once again, Beenemünde's plot to kill Reinhard fails.

The duel between the respective agents of the Schafhausen and Herxheimer families begins. Reinhard von Müsel, sensing a malicious intent from Herxheimer's agent, decides to heed Siegfried Kircheis's advice of leaping sideways the moment the first shot is fired; a technically legal, but frowned upon, move. Both sides thus miss their first shots. In their second shot, Reinhard manages to hit Herxheimer's agent on his right shoulder, while the latter hit Reinhard's left arm. Reinhard realises that had he not used his left arm as a stabiliser to his right hand, the bullet would have hit his chest and killed him. Just as the referee is about to declare Reinhard as the winner based on the results of their second shots, Herxheimer's agent insists on continuing the duel with swords. Despite his injury, he proves to be much more adept with a sword than Reinhard and is about to defeat Reinhard when Imperial Guards under the direct order of Kaiser Friedrich IV suddenly arrive and order the duel to be suspended and the mining rights dispute be resolved by splitting the proceeds equally between the two family. The Schafhausen family is pleased with this outcome while Count Herxheimer accepts it reluctantly.

As news of Reinhard von Müsel's participation in the upcoming duel spread like wildfire within Imperial high society, both Count Herxheimer's agent and Reinhard train hard for the duel. Reinhard, not used to the archaic flintlock pistols that are going to be used in the duel, struggles to shoot properly with them, until an unexpected encounter with Cornelius Lutz who provides him with helpful instructions on shooting with flintlock pistols. Meanwhile, Sussanna von Beenemünde plots to kill Reinhard again by hiring an assassin to do so during the duel. The assassin then kills Herxheimer's agent in a duel challenge to install himself as the duellist representing Herxheimer.

In January 792 UC, after their brief stint aboard the destroyer Hameln II, Reinhard von Müsel and Siegfried Kircheis are transferred to the Investigation Department of the Imperial Ministry of Military Affairs in Odin. Although bored of the clerical work assigned to both of them and frustrated over the atmosphere of corruption and decadence in Odin, Reinhard remains diligent in his duties and is consoled by the fact that he can at least get to visit his sister Annerose von Grünewald. During one such meeting, he learns that one of his sister's friends in the Imperial Court, Viscountess Dorothea von Schafhausen, is currently embroiled in a mining rights dispute with Count Herxheimer, a relative of Marquis Wilhelm von Littenheim. Herxheimer, knowing that he stood no chance of winning through a civil lawsuit, has challenged the Schafhausen family to a duel instead and used his connections to ensure that no professional duellist will duel for the Schafhausen family. Feeling indignant over her predicament, Reinhard volunteers to duel on her behalf.

Reinhard von Müsel proceeds with the plan of using a predicted solar eruption to provide the destroyer Hameln II the necessary speed boost to escape from the rapidly closing in Alliance ambush squadron. One bridge crew member, fearing that the ship will be drawn by the gravity of the star into oblivion if the predicted eruption does not occur, tries to escape in an escape pod but is prevented with the combined effort of Reinhard and Siegfried Kircheis. Meanwhile, repairs on the ship's engines are unable to be completed due to a malfunctioning thruster that has to be repaired from the exterior of the ship. Lieutenant Beltram volunteers to take on this extremely dangerous outboard mission, hoping to atone somewhat for his killing of Rolf Zaidel. He is then paired with Rolf's brother. While the repairs are finished on the nick of time, Beltram and Zaidel are jolted into space as the ship turns to position itself for the eruption. Beltram sacrifices himself to push Zaidel back into the ship, and Hameln II succeeds in escaping from the Alliance ambush. Soon after Hameln II returns to Iserlohn Fortress, Reinhard is promoted for his efforts in saving Hameln II and its crew from possible destruction and he and Kircheis are then transferred to a new posting.

Lieutenant Beltram decides that there is no way to escape from the Free Planets Alliance ambush and plans to self-destruct the destroyer Hameln II and die an honourable death as an Imperial military officer, completely ignoring a plan proposed by Schmidt, an enlisted soldier who studied astrophysics before being drafted into the military. Siegfried Kircheis, after learning about Beltram's plan and his rebuffing of Schmidt, decides to release Reinhard von Müsel from detention, even if that means starting a mutiny. With the help of some enlisted crew members, Kircheis manages to release Reinhard and forcibly take over the bridge of Hameln II. Reinhard decides to implement Schmidt's plan which involves exposing the ship to a predicted solar eruption from a nearby star and make use of the momentum generated to escape the Alliance ambush in high speed. As the crew attempts to repair the damaged ship engines on time for the solar eruption, Beltram succeeds in breaking out of captivity and storms the bridge. A brief confrontation ensues, resulting in the death of Rolf Zaidel and would have escalated if not for the timely intervention of Lieutenant Commander Adenauer, who repeats his order of passing command authority to Reinhard.

During a patrol in the Free Planets Alliance side of the Iserlohn Corridor, the destroyer Hameln II and the unit it is part of is ambushed by an Alliance squadron. Hameln II is struck first, and the resulting damage severely injured the captain, Lieutenant Commander Adenauer, who then passes command authority to Reinhard von Müsel, the highest ranking officer present on the bridge before losing consciousness. Reinhard immediately orders the ship to break course away from the rest of the ambushed patrol unit. When the first officer Lieutenant Beltram arrives on the bridge, he demands Reinhard to pass command authority to him and return the ship to its normal course, but is refused by Reinhard, who claims that it is too dangerous. Reinhard's fears are confirmed when the patrol unit become surrounded and is completely destroyed. After leading the ship to relative safety in a nearby asteroid field, Reinhard finally passes command authority to Beltram, who then promptly orders Siegfried Kircheis to detain Reinhard under the grounds of mutiny.

In August 791 UC, following their transfer out of Kapche-Lanka, Reinhard von Müsel and Siegfried Kircheis are posted to the destroyer Hameln II, currently docked in Iserlohn Fortress, as its chief navigator and security officer respectively. While the captain of Hameln II is impressed of their achievements and welcomed them on board, the rest of the crew are less than enthusiastic, especially the enlisted ranks who view Reinhard's position as a blatant example of favouritism. They then decide to test Reinhard by pitting him with another young enlistee, Rolf Zaidel, on a spacewalk challenge. However, when Rolf lands himself into trouble during the spacewalk, Reinhard risks his life to save him, thus earning him the respect of the enlisted ranks.

Yang Wen-li narrates the findings of his investigation regarding the alleged murder of Free Planets Alliance hero Bruce Ashbey, summarised from Christopf von Köfenhiller's own research, to Alex Cazerne and Dusty Attemborough. Yang surmises that Martin Otto von Siegmeister, having republican tendencies, founded a massive espionage network in the Galactic Empire with the help of Christopf von Michaelsen in an attempt to subvert Imperial rule by leaking confidential military information to the Alliance. Siegmeister, who had defected to the Alliance, found an ally in Bruce Ashbey who proceeded to make full use of Siegmeister's network and heaped victories upon victories in the battlefield. After Ashbey's untimely death during the Second Battle of Tiamat, the network slowly unravelled and ended with the mysterious death of Michaelsen. Upon finishing his narration, Yang adds that the actual truth may not be known until both the Alliance and the Empire cease to exist. A few days later, Yang receives his new appointment as an Operations Staff Officer under the 8th Fleet. Before his departure to the front lines, he attends the wedding of Alex Cazerne and Hortense Milbelle.

Yang Wen-li and Fyodor Patrichev arranges the funeral of Christopf von Köfenhiller on Masszitt and returns to Heinessen, where they bid their respective farewells. Together with Dusty Attemborough, Yang has dinner with Alex Cazerne and meets Cazerne's fiancée, Hortense Milbelle, for the first time. After eating, he begins to report the findings of his investigation into the possible murder of Free Planets Alliance hero Bruce Ashbey.

Yang Wen-li and Fyodor Patrichev, having received transfer orders out of Econia, accompany Christopf von Köfenhiller to Heinessen. During a layover on the planet Masszitt, Köfenhiller recounts his participation of the Second Battle of Tiamat and the circumstances that triggered his interest in investigating the connection between Martin Otto von Siegmeister, Christoph von Michaelsen and Bruce Ashbey. Soon after he finishes his tale, he dies in the spaceport terminal.

Murai, an agent of the Free Planets Alliance military police in Thanatos Starzone, is dispatched to Econia to ascertain the situation. He holds interviews with everyone involved, even peripherally, in the incident. In the end, Barnaby Costea is placed under arrest to be court-martialed for embezzlement and for causing the deaths of those who died in the staged prisoner rebellion, whereas Fyodor Patrichev is given an unofficial reprimand. Alex Cazerne arranges for Yang to be transferred back to Heinessen, and Christopf von Köfenhiller is released from the Econia Internment Camp and granted Alliance citizenship, as well as a military pension befitting his former rank of Captain in the Imperial Fleet.

Captain Barnaby Costea orders the troops under his command to attack the rebelling prisoners, intending to kill both Yang Wen-li and Fyodor Patrichev in the crossfire as he fears they will expose his embezzlement of camp funds. With the help of Christopf von Köfenhiller, Yang, Patrichev and the rebelling prisoners are able to escape the compound. Presberg informs Yang that his rebellion had been staged and that Costea had promised him an early release back to the Galactic Empire if he played along. Yang and Patrichev break into the Econia Internment Camp's command centre and capture Costea. They then report the events that have transpired to the Thanatos Starzone military police.

A prisoner named Presberg takes several Free Planets Alliance officers hostage: Yang Wen-li is ordered to substitute himself, along with Fyodor Patrichev, for the safe return of the hostages. Another prisoner, Christopf von Köfenhiller, also volunteers to be a hostage.

Yang Wen-li travels to his new post on the planet Econia in the Thanatos Starzone. There, he makes acquaintance with Fyodor Patrichev as well as a number of veterans from the Second Battle of Tiamat, including the oldest prisoner-of-war in the Econia Internment Camp, Christopf von Köfenhiller.

Yang Wen-li attends the funeral of Alfred Rosas, and discusses the Year 730 Mafia with Alex Cazerne and Dusty Attemborough. Later, he reviews the fate of the Year 730 Mafia after the Second Battle of Tiamat. Before he can come up with any concrete conclusions however, he is notified of his new appointment in the planet Econia, which hosts a prisoner-of-war camp.

The history of the Second Battle of Tiamat continues to be chronicled. On 7 December 745 UC, having temporarily retreated and regrouped, the Alliance Fleet and the Imperial Fleet engages each other again. Worsening internal conflict amongst the Alliance fleet commanders does not appear to impair their command decisions in the front lines. However, as the battle progresses into a stalemate, the Alliance Fleet is in danger of being completely surrounded by the larger Imperial Fleet. Nevertheless, the Imperial plan fails when Bruce Ashbey, having foreseen this situation, reinforces the besieged Alliance Fleet at an opportune moment, throwing the Imperial encirclement into complete disarray. He is however too late to save Vittorio di Bertini, a member of the Year 730 Mafia. As the Second Battle of Tiamat ends with a major Alliance victory, Ashbey's flagship Hard Luck is struck by stray Imperial gunfire, killing Ashbey in the process. With the end of the chronicling of the Second Battle of Tiamat, Yang Wen-li bid his farewell to Alfred Rosas and returns to his research. However, barely a day has passed when news of Rosas' sudden death is announced.

The history of the Second Battle of Tiamat is chronicled. In December 745 UC, the Free Planets Alliance and the Galactic Empire clashed in the Tiamat Starzone. The Alliance Fleet under the overall command of Admiral Bruce Ashbey is composed of fleets led by members of the famed Year 730 Mafia. There are however signs of internal dissension right before the battle, threatening the morale of the fleet. In contrast, the Imperial Fleet, under the overall command of Fleet Admiral Zieten, is in high spirits, albeit being rather single-minded in hunting down Ashbey. Nevertheless, the battle starts with the Alliance fleet quickly gaining an advantage by succeeding in destroying Vice Admiral Wilhelm von Mückenberger's fleet.

Yang Wen-li reminisces about his days in the Free Planets Alliance Officer Academy spent with Jean Robert Lapp and Jessica Edwards. He later meets with Alfred Rosas to discuss about the latter's past with the Year 730 Mafia and specifically the circumstances surrounding Bruce Ashbey's death.

Yang Wen-li reviews the history of the Year 730 Mafia.

On 19 September 788 UC, Yang Wen-li is promoted to Lieutenant for his efforts in evacuating the civilians of El Facil. Six hours after his promotion, he is promoted again to Lt Commander, making it effectively a double promotion. For the next few weeks, he is thrown into a flurry of events as many people from various sectors of society ranging from the media to his estranged maternal family try to capitalise on his new fame, which he comes to detest. Eventually in October while waiting for his new assignment and avoiding the limelight, Yang is assigned by Alex Cazerne to investigate the Tuesday Correspondence and ascertain the truth behind their allegation that the Free Planets Alliance war hero Bruce Ashbey was murdered.

The first half of the episode covers Yang Wen-li's childhood, and eventual admission to the Free Planets Alliance Officer Academy on Heinessen following the death of his father. The rest of the episode covers the events of the Imperial attack on El Facil, and Yang's leadership of the civilian evacuation that earned him the title, "Hero of El Facil."