It was broadcast on Japanese television from October 5, 1975, to February 27, 1977, and lasted 74 episodes. The robot's first appearance in the United States was as a part of the Shogun Warriors line of super robot toys imported in the late 1970s by Mattel, then in Jim Terry's Force Five series, both under the title Grandizer. It was especially popular in continental Europe and in the province of Quebec as well as the middle east.
Directors: Tomoharu Katsumata, Yoichi Kominato, Yasuo Yamayoshi, Tsunekiyo Otani, Hidenori Yamaguchi, Kazukiyo Shigeno, Yoshikatsu Kasai, Takenori Kawada, Masamune Ochiai, Hiroshi Shitara, Kazuya Miyazaki, Johei Matsuura, Osamu Kasai, Tokiji Kaburaki, Kozo Morishita, Masayuki Akehi, Kazumi Fukushima
Studio: Toei Animation
Network: Fuji Television
Original Run: October 5, 1975 (1975-10-05) – February 27, 1977
The Vega homeworld has become unstable due to the exploiting of Vegatron, a powerful radioactive ore. Seeking to expand his militaristic empire and find a substitute planet to settle upon, the ruthless King Vega unleashes his armies — composed of flying saucers and giant robotic monsters — and turns first against neighbors such as Fleed, a highly advanced but peaceful world. In a tragically ironic twist, the invaders' blitzkrieg turns against them: the once verdant, idyllic Fleed is turned into a radioactive wasteland. Too late, the only known survivor of the royal family, Prince Duke Fleed, manages to steal the Grendizer, the robotic embodiment of the Fleedian God of War, from the Vegan invaders who plan to use it to spearhead their invasion fleet. Grendizer is a giant robot that interfaces with Spazer, a flying saucer that enables the robot to fly.
Fleeing Vegan space by flying at faster than light speed, Duke enters our solar system and switches course to Earth, making a rough landing in Japan, on the slopes of Mount Fuji. He is befriended by Doctor Umon, a noted scientist who oversees a research laboratory called the Space Science Lab near a small ranch. The kindly Umon takes in the young humanoid alien as his son, under the assumed name of Daisuke, and assists him in hiding Grendizer. Taking the name Daisuke Umon, Duke Fleed works at the ranch run by Danbei Makiba (based on Abashiri Daemon of Go Nagai's manga Abashiri Ikka).
Roughly two years later, Kouji Kabuto returns to Japan after studying abroad in a flying saucer he personally designed and built (called the TFO). He heads to the Space Science Lab after hearing of multiple sightings of "flying saucers". He plans to contact the aliens if possible and make peace with them. Daisuke, however, scoffs at the notion and fears that these aliens, the Vegans, led by generals Blaki and Gandal, are preparing to attack Earth. Kouji ignores his warnings and flies out to meet the incoming saucers, only to discover the horrible truth. In order to save Kouji and protect his adoptive homeworld from destruction, Daisuke is forced to return to his true identity as Duke Fleed. He unearths Grendizer from its hiding place under the lab and sets off to fight his enemies.