{ Synopsis }
Warning: Contains spoilers
The year is 1897, and young Olivia Flaversham is celebrating her birthday with her toymaker father, Hiram. Suddenly, a bat with a broken wing and pegged leg bursts into the Flaversham's house, kidnapping Hiram. Olivia searches to find the famed detective Basil of Baker Street but gets lost. A surgeon named Dr. Dawson stumbles upon Olivia, and helps her find the Great Mouse Detective. Upon their arrival at his residence, Basil dismisses Olivia at first, saying he has more important matters to worry about. However, once Olivia mentions the crippled bat, Basil's attitude quickly changes. He explains that Olivia saw Fidget, a henchman of Professor Ratigan, a villain Basil has been trying to arrest for years. Basil agrees to take the case when Fidget suddenly appears, attempting to kidnap Olivia. He is chased away by Basil and Dawson, who then use the dog Toby to track his scent to a nearby toy store.
Ratigan himself, an egocentric, power-hungry renegade scholar, has brought Flaversham to his Center of Operation for a purpose: the creation of a robot which mimics the the Queen Mouse. With the real Queen dead in secret, Ratigan could rule as King of the Mice of England, while the robot verbally supported everything he did. Flaversham refuses, whereupon Ratigan orders Fidget to capture Olivia. If Flaversham refuses to complete the dupe, Olivia will be fed to Felicia, Ratigan's spoiled tame cat.
Fidget is surprised by Basil, Dawson, and Olivia in the toyshop where he is stealing clockwork mechanisms, toy soldiers' uniforms, and tinker's tools for Ratigan's plan. He hides and later traps Olivia by ambushing her from inside a toy cradle. Basil pursues Fidget, but becomes entangled in some toys and falls behind.
While searching the shop, Dawson discovers Fidget's forgotten checklist, which entails everything Fidget has taken with him. Basil and Dawson return to Baker Street, where Basil discovers by means of close examination and some chemical tests that the list was written in the Thames waterfront.
Meanwhile, Ratigan receives from Fidget the supplies needed to create his robot Queen. Olivia and her father are briefly and tearfully re-united, only to be taken apart again when Ratigan orders Olivia held hostage. Ratigan discovers that Fidget has lost the list, and knowing that any detective of Basil's caliber might track its writer, he sentences Fidget to death. Ratigan then realizes how to defeat Basil and pardons Fidget.
Basil and Dawson are enter a tavern called The Rat Trap near the Thames, disguised as ne'er-do-well sailors inquiring for Ratigan. As they wait, they are served two pints of beer. Basil suspects (rightly) that the drinks are drugged, but Dawson has already drunk his. When Fidget stumbles through the pub, Basil decides to follow him, but is momentarily distracted by a fight that has broken out between the staff of the tavern and its customers.
The two follow Fidget through some pipes to Ratigan's headquarters, only to discover that Ratigan has prepared for their coming. The sadistic rat ties them to a spring-loaded mousetrap which, when activated, will break both of their necks. Around them are arranged a pistol, a crossbow, an axe, and an anvil. Nearby is a gramophone. When the record set on it finishes playing, a metal ball will slide down a chute and activate the mousetrap spring. This will set off the gun and the crossbow, which will themselves set off the axe and anvil. A camera will then take a picture of the ending scene.
Ratigan, hinting that he has an engagement at Buckingham Palace, sets off in a dirigible. Basil is altogether crushed by his own failure to see through the trap; he lies bound, feeling sorry for himself, while Ratigan's teasing song plays about his ears. Dawson is most shocked and annoyed at his friend's indifference to their plight and that of the Queen. He indignantly exclaims to the effect that if Basil has given up, why not set the killing machine off before the music is over, rather than wait? This gives Basil an idea; because the trap is set on a delicate balance, setting it off seconds early will cause it to malfunction. To that end, the two mice release the bone-breaking spring at the moment when the metal ball is between their heads. The ball stops the spring in mid-fall, which causes the hinges to break. The hinge tips the gun off balance, where upon its shot sends the crossbow awry. The crossbow fires its arrow into the axe, cutting off the head, which falls between the prisoners, cutting them free. They evade the anvil, free Olivia, and pose for the camera.
Ratigan is putting his plan into action. Hidden behind a curtain, Flaversham operates the toy Queen, while the real Queen is being taken by Fidget to Felicia. At the appropriate moment, Ratigan advances into plain sight, clad in the robes of a King. He at once thanks his Queen-figure, then proceeds to recite a long list of proposed insanely tyrannical legal reforms.
Not far away, Basil's friend, the dog Toby, chases Felicia to a wall. She climbs it easily, but Toby cannot follow her since he cannot climb. She makes a face at him and jumps over the wall, only to be attacked and killed by the Royal Guard Dogs on the other side. Basil, Dawson, and Olivia seize control of the mechanical mouse, forcing it to denounce Ratigan as an impostor and also to shake itself to pieces before the assembled crowd's very eyes. Seeing this, the crowd promptly attacks Ratigan, who manages to snatch Olivia and flee with Basil, Dawson, and Flaversham in pursuit.
On the way, Fidget, who is driving Ratigan's dirigible, becomes tired and suggests that they throw Olivia overboard in order to lighten the load. However, Ratigan, not about to throw away his hostage, throws Fidget overboard instead. The bat falls into the water and is never seen again. Ratigan takes the wheel, but without a helmsman he cannot steer, and winds up crashing into Big Ben. Basil, who has attempted to board his foe's craft, is sent in with them.
Inside the clock, the two adversaries vie for possession of Olivia. Basil traps Ratigan by tossing his cape into the clockworks, and Basil rescues Olivia. The two flee to the top of the tower to the balloon and Olivia is delivered to her father. Ratigan, having lost all pretense or semblance of civilization, tears his cape free and scurries through the clockworks as fast as he can. He becomes ragged and savage as he pursues Basil, finally transforming from a pompous pseudo-gentleman into a huge, terrifying monster. With his tattered cape and clothes, startling agility, and overwhelming girth, he now resembles a maddened demon from a story-teller's nightmare.
Ratigan's only interest is killing Basil; he almost succeeds, but is thwarted when Basil distracts the rat just long enough to keep him from bracing himself when Big Ben rings behind them. The echoes shake Ratigan from his perch on the clock's hands, and he falls to his death, catching hold of Basil and dragging him down. Basil keeps hold of the dirigible's severed propeller, however, and uses it to escape.
Reunited, Olivia and her father depart, promising to remember their friends. Dawson is also willing to leave, but Basil tricks him into remaining by introducing the surgeon to a distraught newcomer as "my trusty associate, Doctor Dawson, with whom I do all my cases". According to Dawson himself, this is true, by all means. And they remain partners thereafter.
--Source: Wikipedia
