"Mobile Suit Gundam Twilight AXIS: Akaki Zan'ei" is a short anime series set in the Universal Century timeline of the Gundam franchise. The story takes place after the events of the Second Neo Zeon War, focusing on the remnants of the conflict and the lingering tensions between Earth Federation forces and Neo Zeon. The narrative centers on two key characters: Arlette Almage, a former Zeon engineer, and Danton Hyleg, a Federation officer. Both are assigned to investigate the abandoned Axis asteroid, a site of historical significance due to its role in past conflicts.

Arlette, who once worked on the development of advanced mobile suits for Zeon, harbors unresolved feelings about her past and the war. Danton, on the other hand, is driven by a sense of duty and curiosity about the secrets Axis might hold. As they explore the asteroid, they encounter remnants of Neo Zeon forces, including a mysterious red mobile suit piloted by a masked individual. This mobile suit, identified as the MS-06R-AB Zaku II High Mobility Type, becomes a focal point of the story, as its presence suggests that Axis may still hold valuable technology or hidden agendas.

The series delves into themes of memory, loss, and the consequences of war, as Arlette and Danton confront their personal histories and the broader implications of their mission. The tension escalates as they uncover evidence of a new mobile suit prototype, the RX-78AN-01 Gundam AN-01 "Tristan," which ties directly to Arlette's past work. The discovery leads to a confrontation with Neo Zeon remnants, forcing the protagonists to grapple with their roles in the ongoing conflict.

"Twilight AXIS: Akaki Zan'ei" is structured as a concise, six-episode series, with each episode running approximately five minutes. Its brevity allows for a focused exploration of its central themes and characters, while also providing a glimpse into the larger Universal Century timeline. The series serves as a bridge between major events in the Gundam universe, offering insight into the aftermath of war and the lingering impact of technological advancements on both individuals and factions.