The race is on! Claus and Lavi enter in a race, that they've entered so many limes before. But this time is different. They hope to finish the race, and they almost do (in 1st place too), but they are hit by a renegade vanship delivering ""cargo"". They soon learn that the ""cargo"" is actually a little girl. Claus decided to take the mission and is told, by Ralph, not to run his engine because the people after the girl can detect it. Just as Claus and Lavi leave the enemy vanship approaches. Now Ralph must make the ultimate sacrifice so that Claus and Lavi can escape with the little girl.

Claus and Lavie decide to assist in defending the Sylvana from the Guild, but do they stand a chance in this fierce battle in the sky?

Following Claus and Lavie aboard the Silvana, Dio and Lucciola allow themselves to be captured. At the Anatoray capital, the Emperor begins to distrust Alex's actions and sends the Urbanus to retrieve Alvis. Alex interrogates Dio, who tries to gain his trust by telling him that the Mysterion passed by House Eraclea. He also reveals that the three Guild houses holding the remaining Mysteria have been purged by Delphine. Vincent Alzey, captain of the Urbanus, requests to meet with Alex. Alex asks Claus to fly escort for his flight to the meeting, to which Tatiana objects. Alister defies Tatiana and offers to be Claus's navigator. Alex informs Vincent that he will not hand over Alvis and will fight to keep her aboard. Dio and Lucciola meet Lescius, the Silvana's chief engineer and a former member of the Guild. Dio then finds Alvis by herself elsewhere and reads her one of the Mysteria, after which she falls into a trance and wreaks havoc on the ship's systems.

Sophia leaves the Silvana to return to the Anatoray capital. When General Vitellius informs the Emperor that Duke Mad-thane has engaged the Disith fleet in Norkia, Prime Minister Marius pleads with him to spare the Disith, who have recently lost their homes. However, the Emperor has already put the Disith envoy to death and places Marius under house arrest. Mullin begins to question why he remains on the Silvana, and reminisces his days as a musketeer. Alex finally considers launching a strike at the Guild, and Claus reveals to Lavie that their vanship belonged to Alex. When Sophia arrives at the capital, she also pleads with the Emperor to set aside differences with Disith and face their challenges together, but he declines and imprisons her in the tower. Sophia is visited by Marius, who raised her after his daughter Euris died in the Grand Stream, and is asked to remain in the tower until after his plans for her to become Empress is completed. That evening, Disith forces make a surprise attack on the Anatoray capital, whose defense fleet is stretched thin. In the confusion, Marius assassinates the Emperor but is fatally wounded himself. As Disith forces enter the capital, Vincent heads to the tower to prevent the Emperor's men from killing Sophia and takes her to safety on board the Urbanus, taking command of the ship again.

As the Silvana and the Urbanus continue their search for Exile, Sophia briefs the vanship pilots on their strategy to capture it. Sophia asks Dio to fly as Claus's navigator, but he refuses from fear of being found again by Delphine. At Horizon Cave, Nestor proposes that the Claudia unit capture plan be accelerated after the Guild recalls several units, but Duke Mad-thane appeases him to wait for the scheduled operation on Covenant Day. On the final day of the Guild's Birth Week, Alvis surprises Dio with a birthday party, much to his delight. After days of searching, the Silvana and the Urbanus locate Exile, and Dio agrees to fly as Claus's navigator to assist in its capture. The Guild locates Dio on board the Silvana, and Delphine orders Lucciola's brother Cicada to retrieve him at all costs. As the vanship squadron attempts to anchor cables onto Exile, the ship's defense system activates, but it is able to complete their objective after identifying an unprotected section of the hull, with Dio's help. Alex hands Marius's Mysterion to Sophia and tells her to return to the Urbanus. Just before Claus and Dio return to the Silvana, Guild fighters land on the flight deck.

When Claus and Dio return to the Silvana, the crew is missing. When they go to search the bridge, they find that Delphine has captured Alvis and the ship. Tatiana and Alister sneak a transport carrying Sophia back to the Urbanus. Alex comes out of hiding to attack Delphine but is defeated by Cicada. Delphine takes Dio back to the Guild along with Claus, Alvis, and Alex, and orders that Exile be secured before they leave. On the Urbanus, Vincent promises Sophia that he will recapture the Silvana. When they return to the Guild, Dio is taken to prepare for the Rite of the Covenant. Delphine indulges in the world's rarest delicacies at dinner, causing Claus to become upset about her disregard of the hardships of the people of Anatoray and Disith. Dio is reunited with Claus and Alvis, but they find that his personality has changed and he no longer recognizes them as friends.

Princess Liliana is sent to Iglasia with instructions for defending the royal city from the Federation assault. Meanwhile, Princess Millia readies a surprise attack of her own, but little does she know Luscinia has a trick up his sleeve too...

Much to Fam and friends' elation, Turan and Anatoray form an alliance with Millia and Vincent acting as delegates. Suddenly the Impetus, an Ades Federation flagship, appears... along with Luscinia and Liliana.

Upon hearing Sārā's wish, Admiral Sadri agrees to peace. A meeting takes place between Luscinia, Liliana, Sārā, Millia, Vasant, and others.