Open file in chess is a file with no pawns of either color on it. An open file can provide a line of attack for rooks or a queen, just like the sky pirates and the Royal flagship's joint effort to deceive the Ades Fleet. Fam Fan Fan and Giselle Collette are Sky Pirates who ride smaller vanships called Vespas where they capture battleships with other Sky pirates led by Giselle's father, Atamora, with Dio also a member as well. Meanwhile at the Grand Lake, the Princesses of the Kingdom of Turan, Liliana il Grazioso Merlo Turan and her younger sister, Millia il Velch Cutrettola Turan, are preparing for a peace treaty with the powerful Ades Federation led by Premier Luscinia H?fez, Liliana childhood friend. However, the peace treaty is a ruse to capture the princesses which the larger Ades fleet attacks the unprepared Turan fleet. The Sky Pirates learn of the attack and head to the Grand Lake where Fam offers to rescue the Princesses in exchange they surrender their flagship Lasas to them which Liliana agrees much to Millia's shock. Thanks to Fam and the Sky Pirates, the Ades fleet is tricked into shooting each other due to smokescreens and faked light signals and the fleet is fooled into believing the Lasas has sunken. Now under the safety of the Sky Pirates, Liliana orders to head back to the Turin capital Iglasia to prepare for Luscinia's next attack.