Dai-Guard: Terrestrial Defense Corp.

Twelve years ago, Japan was attacked by a Heterodyne, a mysterious monster that seemingly appeared out of nowhere. In response, 21st century Security built a giant robot called Dai-Guard to combat the Heterodyne, but by the time it was ready, they had disappeared again. Turned over to the company's PR division, Dai-Guard has since become little more than a tourist attraction. However, when the Heterodyne reappear, PR Division worker Akagi Shunsuke is insistent that he and his co-workers should pilot the robot for the purpose it was meant for.

Against the wishes of both the Army and 21st Century Security, Akagi and the rest of PR Division decide to help those hurt in the Heterodyne attack by flying them to a hospital. As if dealing with army and company politics wasn't enough, the situation only gets worse when the Heterodyne resurfaces for a second attack.

The fighting may be over, but the paperwork is just beginning, as damage claims and lawsuits related to Dai-Guard's last mission start piling up. Whilst the rest of PR Division 2 buckles down to tackling the economical fallout, Aoyama decides that he wants nothing more to do with Da-Guard, and quits his job.

With rumors flying around about a new division being created to take charge of Dai-Guard, the team decides to demonstrate that they are the best people for the job. Ordered to capture the next Heterodyne instead of destroying it, the pilots head into battle under the watchful eye of their new tactical advisor, Agent Shirota. And Ibuki especially feels she must prove her worth after her father asks her to quit.

Faced with the prospect of having to turn Dai-Guard over to the army, Akagi becomes determined not to make a single mistake.

News of the rebuilding of the old park sparks Ibuki's old memories of playing there with her father.