"Super Mobile Legend Dinagiga" is a science fiction mecha anime series set in a futuristic world where humanity faces existential threats from colossal alien entities known as the Gigas. The story centers around a group of young pilots who operate advanced biomechanical robots called Dinagigas, designed to combat the Gigas. These machines are unique in their ability to synchronize with the pilots' neural patterns, granting enhanced control and combat efficiency.

The protagonist, Kaito Tachibana, is a skilled but emotionally reserved pilot who becomes the primary operator of the flagship Dinagiga unit, designated as "D-01." Kaito's journey begins when his hometown is destroyed by a Gigas attack, leaving him with a deep-seated desire for vengeance. As the series progresses, Kaito is joined by a diverse team of pilots, each with their own motivations and personal struggles. Among them are Aya Fujisaki, a determined and compassionate co-pilot, and Ryoma Kurogane, a hot-headed rival with a mysterious past.

The narrative unfolds through a series of escalating battles against increasingly powerful Gigas, revealing that these entities are not mindless destroyers but part of a larger, enigmatic agenda tied to the origins of the Dinagiga technology. The pilots uncover secrets about the true nature of the Gigas, their connection to humanity's history, and the ethical dilemmas surrounding the use of the Dinagiga units. Themes of sacrifice, camaraderie, and the cost of war are explored as the characters grapple with their roles in a conflict that threatens to consume both sides.

The series balances intense mecha combat with character-driven drama, delving into the psychological toll of piloting the Dinagiga units and the bonds formed between the team members. As the story reaches its climax, the pilots must confront the ultimate Gigas, a being of unimaginable power that challenges their resolve and forces them to make life-altering decisions. The conclusion ties together the series' central themes while leaving room for interpretation regarding the future of humanity and its relationship with the Gigas.