"After War Gundam" is set in a post-apocalyptic future where Earth has been devastated by a catastrophic conflict known as the "7th Space War." The war left the planet in ruins, with much of its surface uninhabitable and society fractured into scattered settlements. The story begins 15 years after the war, focusing on a young scavenger named Garrod Ran, who stumbles upon a functional mobile suit, the Gundam X, while exploring the wastelands. This discovery sets him on a journey that intertwines his fate with the remnants of humanity and the lingering consequences of the war.

Garrod encounters a mysterious girl named Tiffa Adill, who possesses Newtype abilities—psychic powers that were highly sought after during the war. Tiffa is being pursued by the New United Nations Earth (NUNE), a militaristic organization attempting to rebuild civilization under its control. NUNE seeks to harness Newtypes for their own purposes, viewing them as tools to maintain power. Garrod, driven by a mix of curiosity and a desire to protect Tiffa, becomes embroiled in the conflict between NUNE and the resistance group known as the Vulture, who oppose NUNE's authoritarian rule.

As the narrative progresses, Garrod and Tiffa are joined by a diverse cast of characters, including Jamil Neate, a former Gundam pilot from the 7th Space War who now leads the Vulture. Jamil serves as a mentor figure to Garrod, offering guidance and insight into the complexities of war and peace. The group travels across the ruined Earth, encountering various factions and individuals, each with their own motivations and struggles. Themes of survival, redemption, and the search for a new purpose in a broken world are central to the story.

The plot delves into the ethical dilemmas of using Newtypes as weapons, the scars left by war, and the possibility of rebuilding a better future. Garrod's journey is one of growth, as he evolves from a self-interested scavenger to a determined protector of those he cares about. Tiffa's role as a Newtype becomes increasingly significant, as her abilities hold the key to understanding the past and shaping the future. The series balances action-packed mobile suit battles with introspective moments, exploring the human cost of conflict and the resilience of the human spirit.

"After War Gundam" stands out for its exploration of a post-apocalyptic setting within the Gundam universe, offering a fresh perspective on the franchise's recurring themes. The narrative is driven by its characters' personal struggles and the broader societal challenges they face, creating a compelling and thought-provoking story.