Radiguet is the main antagonist of Choujin Sentai Jetman. He is one of the generals of the outerwordly group of Vyram, bent on conquering the galaxy all for himself instead for his group and destroy any who gets in his way.
Originally, Radiguet was a servant of Vyram's leader Juuza until her disappearance during their conquest of the Back Dimension left a power vacuum. Being the first of Vyram to declare the group's intention for the invasion of Earth, Radiguet he demanded subjugation and decimated the Skyforce base in space, indirectly spreading the Birdonic Aura to Earth where four unassuming civilians became members of the Jetman team. In the process, an officer by the name Rie Aoi was sucked out of the space with Radiguet saving her life to convert her into one of Vyram's elites: Maria. Shortly after, the invasion to Earth began, the Vyram received resistance in form of the Super Sentai team known as Choujin Sentai Jetman. After recognizing the resistance, Radiguet made a bet with his fellow elites Tran, Grey, and Maria: Whoever defeats the Jetmen first will become the new leader of Vyram.
When Juza returned to power, motivated by his pride, Radiguet attempts to kill her and ends being punished for his treachery by living as a human with no memory of his life in Vyram. Cared for by Saki, a girl on the verge of death, Radiguet unconsciously saves her life with his power. But though he wanted nothing to do with his past, Radiguet eventually regains his memories and helps the Jetmen in fighting Juuza. After killing Juuza, Radiguet was confronted by Saki, who begged him to return being human, pointing out that he is capable of kindness. But Radiguet kills her without a second thought before taking the Semimaru egg on Juza's person and nurtured it to fight the Jetman before it was destroyed by Jet Garuda.However, when a fed-up Tran matures into Tranza, Radiguet is forced to acknowledge him as their leader for the moment while sabotaging his Veronica robot. However, found out hooked up to have his life force sucked out, Radiguet drains Veronica's power. Later, after using the Jetmen to do his dirty work, Radiquet tortures Tranza before breaking his mind and leaving him powerless, becoming Vyram's leader. Ultimately, the side effects of his power boost manifest in his newly gained giant form, the armored Raguem. It was after Maria fully regained her memories as Rie, Radiguet killed her so Ryuu can not have her back. Soon after, Radiguet challenges furious Red Hawk to a final battle. However, his friends snapped him out of it and with a goal of protecting the people instead of revenge, Ryuu led the Jetman team to defeat Radiguet as he reveals Raguem form to overpower Great Icarus. When Tetra Boy exposes the weak point Rie made on Radiguet, attempted to assimilate the Vylock into armor before Jet Garuda rips the armor off and sacrifices itself so Great Icarus can destroy Raguem as he tells the Jetman that he will have revenge on them even beyond death.
In the non-canon manga, Radiguet's spirit existed long enough to eventually possess Tranza's vegetative body and resumed his reign of terror, this time focusing more on the vengeance on the Jetman. He also possessed the daughter of Ryuu and Kaori Rokumeikan/White Swan to terrorize them, and when that failed, he possessed the replacement of the deceased Gai Yuuki/Black Condor, the rock star Jeffrey Kensaki/Green Eagle. However, Jeffrey mustered enough willpower to banish Radiguet from his body. Before he could possess another body, Radiguet's spirit was stopped by Tranza's spirit, who drags him to Hell and destroys him forever.