"Moriarty the Patriot" is a reimagining of Arthur Conan Doyle's Sherlock Holmes stories, centering on William James Moriarty as the protagonist rather than the antagonist. Set in late 19th-century Britain, the series explores the rigid class system and societal inequalities of the era. William, a brilliant mathematician and nobleman, adopts the alias of a consulting criminal to dismantle the corrupt aristocracy and create a more equitable society. Alongside his adoptive brothers, Albert and Louis Moriarty, he orchestrates elaborate schemes to expose and eliminate corrupt figures, often manipulating events to appear as accidents or unrelated crimes.

The narrative is divided into two main arcs. The first arc focuses on William's early life and his rise as a mastermind. Born into poverty, he is adopted by the Moriarty family, where he witnesses firsthand the cruelty of the upper class. This fuels his resolve to reform society, even if it means resorting to morally ambiguous methods. The second arc delves into his escalating conflict with Sherlock Holmes, who emerges as a formidable adversary. Holmes, a consulting detective, begins to unravel Moriarty's plans, leading to a high-stakes intellectual battle between the two. Their dynamic is characterized by mutual respect and rivalry, as both recognize each other's genius while standing on opposing sides of justice.

Key characters include William James Moriarty, whose calm demeanor and strategic mind drive the series' central conflicts; Albert Moriarty, the eldest brother, who supports William's vision while grappling with his own moral dilemmas; and Louis Moriarty, the youngest, who serves as William's loyal confidant and enforcer. Sherlock Holmes is portrayed as a sharp, eccentric detective whose deductive skills challenge Moriarty's schemes, while John Watson provides a grounded perspective as Holmes's companion. The series also introduces original characters, such as Fred Porlock, a skilled informant working for Moriarty, and Irene Adler, who plays a pivotal role in the unfolding drama.

The plot intertwines episodic cases with an overarching narrative, blending mystery, action, and psychological intrigue. Each episode often presents a self-contained story involving a specific target of Moriarty's plans, while gradually advancing the larger conflict between Moriarty and Holmes. Themes of justice, morality, and the consequences of ambition are explored through the characters' actions and decisions, offering a nuanced portrayal of their motivations. The series concludes with a climactic confrontation that leaves the fates of its central figures unresolved, reflecting the enduring tension between their ideals.