The compilation film will recap the anime's 59 episodes from seasons one to three.

Haru Nabatame, Rio Seibu, and Kyouka Tamaki's idol unit, TiNgS, is on the verge of disbandment. However, if they can fill all two thousand seats in their upcoming anniversary concert, their idol careers will live to see another day. This quota is seemingly impossible for a group like them, especially when the most people they have had at a show is 37. Fortunately, they are placed under a new talented manager—Naoki Hinase. While initially reluctant due to past experiences, Naoki takes charge of TiNgS after sensing Haru's genuine passion for idols with his own remarkable ability to see the shine of someone who is lying. Despite the challenges she faces in this ambitious endeavor, Haru wants everyone in the world to love idols, even willing to become the shining guidepost—shine post—to accomplish her dream.

Thousands of years ago, the ancient dragon Bahamut wrought havoc upon the land of Mistarcia, a world where both gods and demons live amongst mankind. Working together to prevent the world's destruction, the rival deities barely managed to seal Bahamut, agreeing to split the key between them so that the dragon would remain eternally imprisoned. With the world safe from the destruction of Bahamut, it is business as usual for bounty hunters like Favaro Leone. Living a laid-back, self-serving lifestyle, the amoral Favaro goes about his work while on the run from fellow bounty hunter Kaisar Lidfard, a righteous man who swears vengeance upon Favaro. However, Favaro's carefree life is thrown into chaos when he meets Amira, a mysterious woman who holds half of the key to the world's fragile peace. Shingeki no Bahamut: Genesis tells the story of a group of unlikely heroes who find themselves caught in the middle of an epic clash between gods and demons, forced to carve their own path in the face of the imminent storm.

The first short story focuses on Favaro and Kaiser between the events of the first and second series as they visit Favaro's home village. The second short story shows Kaiser as a knight commander sparring with Jeanne, and sharing the reasons they remained as Orleans Knights in the aftermath of the final battle against Bahamut.