Professor Padraic Ratigan is the villain of Disney's The Great Mouse Detective, voiced by the late Vincent Price. He is the story's version of Professor James Moriarty from Arthur Conan Doyle's Sherlock Holmes stories, and serves as the adversary to the Sherlock Holmes counterpart, Basil of Baker Street. He has cited "The Big Ben Caper" and "The Tower Bridge Job" as two of his most notorious criminal operations. He has variety of henchmen that follow him, including his overweight pet cat Felicia, and his right-hand man, a peg-legged bat named Fidget. Even though he is a rat, he is offended by being called one, however, he can easily be identified as a rat since he has four fingers and a thumb on each hand while all the other mice have three fingers.

Ratigan makes plans to take over Mousedom by replacing the queen with a robotic fake built by a toymaker named Hiram Flaversham, whom he has Fidget kidnap. Basil and Doctor Dawson foil these plans with help from the toymaker's daughter, Olivia. Ratigan falls to his death in an epic confrontation with Basil on Big Ben's clock hands, in a scene similar to the Battle of Reichenbach Falls in Doyle's story "The Final Problem."

Ratigan hates being called a 'sewer rat', preferring the description of 'a big mouse', and even orders one of his henchmen fed to Felicia when said henchman calls him "the world's greatest rat". Despite his hulking, brutish stature, he presents himself as a sophisticated dandy, constricting his enormous body to the near-bursting confines of a suit and sporting such trivial accessories as a cravat, white opera gloves and a cigarette holder. In an effort to obliterate any signs of lower breeding from his personality, he adopts delicate mannerisms, typically walking on his toes, throwing himself into melodramatic poses, gasping and reciting speeches in theatrical excess and ringing a small, golden bell with his little finger extended to summon his cat. Despite this facade, however, his beastly and vicious nature is all too evident, and he is prone to explosive bouts of violence (including the aforementioned "world's greatest rat" scene, as well as fatally tossing Fidget off of his personal zeppelin in order to "lighten the load") whereupon he must consciously suppress himself back into his 'dandified' persona. When his plans have failed during the movie's climax, his mind finally snaps, and he at last reveals himself for the animal he truly is, shredding his clothing, extending his claws through his gloves, and falling to all fours in a psychopathic rage, any pretenses of civilization abandoned.