"Mobile Suit Gundam 0083: Stardust Memory - The Mayfly of Space 2" is a direct continuation of the "Mobile Suit Gundam 0083: Stardust Memory" OVA series, set in the Universal Century timeline. The story unfolds in UC 0083, three years after the One Year War, as the Earth Federation and the remnants of the Principality of Zeon continue their conflict. The narrative centers on the theft of the prototype Gundam GP02A "Physalis," equipped with a nuclear warhead, by former Zeon ace Anavel Gato. Gato, driven by his loyalty to Zeon's ideals, aims to use the Gundam to strike a decisive blow against the Federation.

The Earth Federation assigns rookie pilot Kou Uraki to pilot the advanced Gundam GP01 "Zephyranthes" and pursue Gato. Kou, initially inexperienced, grows into a capable pilot as he faces the challenges of combat and the moral complexities of war. The story also explores the dynamics between Kou and Nina Purpleton, a Federation engineer and Kou's love interest, whose past connections to Gato add emotional tension to the narrative. Meanwhile, the Albion, a Federation ship, becomes the focal point of the pursuit, with its crew working tirelessly to recover the stolen Gundam and prevent a catastrophic attack.

As the conflict escalates, the Delaz Fleet, a Zeon remnant faction led by Aiguille Delaz, orchestrates Operation Stardust, a plan to drop a colony onto Earth, crippling the Federation's military and political power. The Federation's internal divisions and political maneuvering further complicate the situation, as factions within the military prioritize their own agendas over the greater good. The climax of the story sees Kou and Gato engage in a final, high-stakes battle, with the fate of Earth and the balance of power in the Universal Century hanging in the balance.

The series delves into themes of loyalty, sacrifice, and the human cost of war, while showcasing intense mobile suit battles and strategic warfare. Characters like Kou, Gato, and Nina are portrayed with depth, their personal struggles and motivations driving the narrative forward. The story serves as a bridge between the events of the One Year War and the rise of the Titans in later Universal Century timelines, highlighting the ongoing tensions and consequences of the Federation-Zeon conflict.