Basil of Baker Street is the main protagonist of the 1986 Disney classic The Great Mouse Detective.
Role in the film
Basil of Baker Street is assigned on a new case- with an old enemy behind it! When eight year old Olivia Flaversham is in a dire hour of need, Basil must take all of his intelligence, skills of deduction and his courage, not to mention the loyalty of his friends-Toby the basset hound, Olivia, and Doctor David Q. Dawson, a kindly mouse surgeon who had just returned to London- to save Olivia's father, redeem the Empire from a nefarious dictator and defeat Professor Padraic Ratigan, Basil's arch nemesis, before it's too late...
Basil is a "thumb sized Sherlock Holmes." With astonishing powers of deduction, the ability to play violin and many more talents, he could almost be the "Great Detective" in mouse form. He has little regard for most people, and sees people who come for his assistance as mere clients. However, from the instant Dawson and Olivia walked through the door of 221 1/2 Baker Street, well that's something else! Despite his "lone wolf" impression, he is capable of showing affection, as he does admit Olivia is "not a bad little girl, actually," and also, after losing his temper with Dawson -once Fidget escapes- a guilty detective amends his mistake.