"Gundam Build Divers Re:RISE" is a 26-episode anime series set in the "Gunpla Battle Nexus Online" (GBN), a virtual reality game where players pilot customized Gunpla models. The story centers on Hiroto Kuga, a skilled but reclusive GBN player who is invited to join a team called "Build Divers" by a mysterious girl named May. Initially hesitant, Hiroto eventually agrees, joining teammates Kazami, a brash and ambitious pilot; Parviz, a cheerful and resourceful engineer; and May, who harbors a secret connection to the game's world.

The team embarks on quests within GBN, but their journey takes an unexpected turn when they discover that the game's virtual world is intertwined with a real, parallel universe called Eldora. This universe is under threat from an alien race known as the One-Eyes, who are attacking its inhabitants. The Build Divers realize that their actions in GBN have real consequences in Eldora, and they are drawn into a conflict to protect its people.

As the story progresses, Hiroto and his team uncover deeper mysteries about Eldora, the One-Eyes, and the true nature of GBN. Hiroto, in particular, grapples with his past failures and guilt, which are tied to a previous team he abandoned. The narrative explores themes of redemption, teamwork, and the blurred lines between virtual and real-world responsibilities. The Build Divers form alliances with Eldora's inhabitants, including a young girl named Freddy, who becomes a key figure in their mission.

The series builds toward a climactic battle against the One-Eyes, with the Build Divers leveraging their skills and the unique capabilities of their Gunpla to protect Eldora. The resolution ties together the personal arcs of the characters, particularly Hiroto's journey toward self-forgiveness and growth. The story concludes with a sense of closure for the team's adventures while leaving room for future possibilities within the GBN universe.