William James Moriarty lives as a regular noble while also being a consultant for the common folk to solve their problems. However, deep inside him lies a desire to destroy the current structure that dominates British society.

In the late 19th century, the British Empire has become a global power. Due to the strict class stratification, the average citizen has little chance of successfully rising up to the top, where the despicable nobility rules over them all. William James Moriarty, the second son of the Moriarty household, is a young mathematics professor who has displayed great cunning and intellect since he was a child. Along with his brothers Albert and Louis, he lives the simple life of a noble. Outside of school, William is a well-known private consultant willing to solve the problems of anyone in need. However, his gentle demeanor belies his position as the head of a group prepared to wreak havoc in pursuit of its desire-a new world built from the ashes of the old. Yuukoku no Moriarty puts a new spin on Arthur Conan Doyle's original work by putting the spotlight on its main antagonist and exploring how he came to be the first and only "criminal consultant."—MAL Rewrite

In the late 19th century, the British Empire nobility reigns while its working class suffers at their hands. Sympathetic to their plight, William James Moriarty wants to topple it all. Frustrated by the systemic inequity, Moriarty strategizes to fix the entire nation. Not even consulting detective Sherlock Holmes can stand in his way. It's time for crime to revolutionize the world.—themoviedb

William James Moriarty vive una vida típica de noble pero también trabaja como consultor para ayudar a las personas comunes a resolver sus problemas. No obstante, en su interior se encuentra un anhelo de desmantelar la estructura actual que gobierna la sociedad británica.