Dragonar takes place in the year 2087 AD, when a military force called the United Lunar Empire Gigano has risen and captured the Moon. Their stated goal is the rebirth of mankind, but their primary intention by some of its members is the destruction of all those who dwell on Earth. To this end, the Empire uses humanoid battle machines called Metal Armors, as well as a gigantic mass driver cannon. Originally intended to send lunar material to Earth orbit for later retrieval, the Mass driver is reconfigured to launch small meteorites towards the home world. By the time the story takes place many bombardments have already taken place. The Earth Alliance became the Earth Federation military, unable to compete with the Giganos military might, manages to steal three prototype Metal Armors, called the Dragonars, with plans to reverse-engineer them with the help of exiled Giganos scientists. However, the ship carrying the Dragonars (posing as a refugee ship) is chased to a neutral colony by Giganos, and an attack is staged to retrieve them. Kaine, Tapp and Light, three friends and EFM trainees, are on the colony during the attack, and find a dying Giganos spy who gives them three disks.
