"Fate/Zero" is a Japanese light novel series written by Gen Urobuchi and illustrated by Takashi Takeuchi. It is a prequel to the visual novel "Fate/stay night" and is set in the Fourth Holy Grail War in Fuyuki City, where seven magicians (Masters) and their magical spirits (Servants) battle each other to claim the Holy Grail. The story revolves around Kiritsugu Emiya, an unconventional magician who believes that one person's wish can change the world. He forms an alliance with the Servant Saber, but their path is filled with moral dilemmas and sacrifices. "Fate/Zero" is celebrated for its complex characters, intricate plot, and emotional depth. It has been adapted into an anime series, which gained significant popularity due to its stunning animation, compelling storytelling, and mature themes.