Nicknamed "Tetsujin," it was developed by Dr. Kentaro Kaneda, Shotaro Kaneda's father, but was killed mid-development by Branch, who targeted the solar energy conversion system that powered it. Dr. Daijiro Shikishima then took over and perfected it.

Tetsujin is unique in that it is not directly mounted on the robot, but is remotely controlled by a remote control called a "V-Con (officially known as a Vision Controller)." However, as the lyrics of the theme song for the original animated series "Tetsujin 28" suggest, "Good or bad, it depends on the remote control," the remote control can be stolen and misused by villains. Furthermore, its remote control system is also its greatest weakness, as it can lose control due to radio interference and can only be controlled within the visible range.

It is usually stored in a hangar beneath the tennis court at the Shikishima residence. Its independent interlocking system allows it to continue operating even if part of the robot is destroyed. It also emits a roaring sound when activating. In the film, it is recognized by the Guinness Book of World Records (in the film) as the world's best robot in four categories: height, weight, power, and speed.

Unlike the original work, the original anime, "FX," and the 2004 version of "Tetsujin 28," it has an overall sleek form, no visible pupils, and is characterized by the number "28" markings on both arms. Its exploits in the film are also more like those of a super robot.