Fate/stay night is a Japanese visual novel and anime series created by Type-Moon. The story follows a high school student named Shirou Emiya, who becomes embroiled in a battle between seven mages known as "Masters" who summon legendary heroes known as "Servants" to fight for the Holy Grail, a powerful artifact that grants wishes.
The story is divided into three main routes, each following a different heroine: Saber, Rin Tohsaka, and Sakura Matou. In the "Fate" route, Shirou forms a contract with Saber and fights to protect her while also trying to win the Holy Grail. In the "Unlimited Blade Works" route, Shirou forms a contract with Rin and becomes embroiled in a battle between rival mages. In the "Heaven's Feel" route, Shirou forms a contract with Sakura and delves into the darker side of the Holy Grail War, uncovering secrets about the true nature of the Holy Grail and the motivations of the various characters.
The characters in Fate/stay night are complex and well-developed, with each one having their own backstory, motivations, and personal issues. The relationships between the characters are also a major focus of the story, with many of the characters' actions being driven by their feelings for others. The animation and artwork for the series is also well-done, with detailed and visually striking fight scenes.
The Fate/stay night franchise has also spawned several spin-offs and adaptations, including the anime series Fate/zero, which tells the story of the previous Holy Grail War, and the anime film Fate/stay night: Heaven's Feel, which adapts the third route of the visual novel. The franchise has also spawned manga, light novels, and video games.
Overall, Fate/stay night is a well-written and visually stunning series that appeals to fans of fantasy, action, and romance. The complex characters, intricate plot, and stunning animation make it a must-watch for fans of the genre. The franchise has also expanded to many other mediums, making it easy for fans to explore the world of Fate/stay night in different ways.