The Great Mouse Detective is owned by Disney and Eve Titus. I don't own it and make no claims to the contrary.
I always found it ironic that the final battle of the movie took place in Big Ben when Ratigan mentions it as the site of a famous earlier crime of his during "The World's Greatest Criminal Mind" and felt the need to write a fanfic describing his thoughts of getting rid of Basil at the exact location of one his greatest criminal triumphs. So here it is for you to enjoy.
As a side note, this also makes reference to the deleted lyrics of "The World's Greatest Criminal Mind" found on the Disney Read-Along Storybooks & Cassettes version of The Great Mouse Detective which can be found on YouTube if you want to find it (though you'd have to settle for it being sung by Corey Burton rather than Vincent Price if you do).
Coming Full Circle
As he silently made his way across the clock gear, his hand muffling Flaveshem's daughter from warning the detective, Ratigan couldn't help but appreciate the irony of finishing Basil off at the site of his first big crime. The nefarious Professor always had had fond memories of Big Ben. After all, this was the place where he'd first carved a name for himself in the annals of crime, the place where he'd "hampered time and became a myth." And now, if he was going to have any say in it, it would be the place where he'd finally rid himself of the insufferable pipsqueak who'd made his life hell for the past several years and get revenge for having his would-be coronation tonight thwarted.
The girl finally broke free of Ratigan's grasp, shouting out a warning to the detective. But by then, it was already too late as Ratigan backhanded Basil just as his smaller opponent started to turn around, sending the detective stumbling towards the edge of the gear. Basil was barely able to grab onto its side, preventing himself from falling into the near-endless abyss of the clockworks, a fate that had befallen one of Ratigan's more stupider henchmen during the Big Ben Caper. As the detective struggled to pull himself back up onto the gear's surface, Ratigan marched over, determined to finish the job, only for his prisoner to suddenly bite upon his hand, causing the Professor to shriek with pain.
Basil soon took advantage of this distraction as he leapt back onto the clock gear, grabbing Ratigan's cape and ensnaring it between two nearby clock gears, choking the larger rodent. Struggling to free himself from its oppressive grip, the Professor inadvertently kicked Flaveshem's daughter off the gear they were currently on onto another giant gear that was on the verge of grinding itself with another gear. Seeing this, Basil soon leapt off the gear he was currently on onto a rising chain, leaving his longtime enemy to his own devices.
Still struggling to free himself from his own cape, Ratigan managed to catch a glimpse of Basil pulling the little girl to safety just in time as they used the chain to rise up to safety at the very top of the clockworks. Ratigan's eyes widened in anger and disbelief. This was not acceptable!
He would NOT be made a fool of at the site of his greatest criminal triumph!
Immediately, something inside of the Professor seemed to snap. Finally succumbing to the "inner rat" that he'd spent years attempting to suppress for the sake of gentlemanly appearances, Ratigan gave a roar of fury as he shredded off his gloves, revealing long sinewy hands which he used to rip himself free of his cape and the chokehold it was putting him in. His mind in a feral state, the mouse- No, rat, he corrected himself- bounded up the clockworks on all fours, using long-forgotten memories of the mechanics and design of Big Ben from his first crime to provide him with shortcuts in catching up with Basil and his young companion.
He soon arrived at the top of the clock tower just in time to see the detective handing the little girl over to her father on the balloon. Unfortunately, focusing his attention on bringing the child to safety proved to be a fatal distraction for Basil as immediately upon handing her to her father, Ratigan tackled the detective, sending the two of them falling towards the clock hands below.
Ratigan barely noticed that it had begun raining as he crouched in the shadows of the clock hands, waiting for the perfect moment to strike. The opportunity soon presented itself as Basil became distracted by his companions attempting to lower the balloon for him to leap on. Immediately, Ratigan lunged out of the shadows, grabbing his smaller opponent from behind. Barely wriggling himself free from his opponent's grasp, the detective attempted running up the hour hand towards his companions, only for the maddened Professor to leap in front of him, cutting his path off. "There's no escape this time, Basil," sneered Ratigan. "There's nowhere you can flee to on this clock that I'm not already well-aware of!"
Basil immediately tried fleeing in the opposite direction, only for the larger rodent to once again leap in front of him, cutting his path. Tired of the rat-and-mouse game he was playing with the pipsqueak, Ratigan soon began swiping at the detective, knocking him all over Big Ben's hour hand. One final uppercut sent Basil flying off the clock hand, the detective barely able to grab onto its edge.
Staring down at his long-time enemy, Ratigan began relishing the moment as he raised his hand into the air, the lightning strike occurring at that moment providing the perfect atmosphere for what he was about to do. One last time, Ratigan swiped down at the detective, dislodging his grip, and sending him falling down to the Thames River below. Basil's companions on the balloon attempted to reach out to save the detective, only for him to fall just out of their reaches.
Upon seeing this, Ratigan grinned in triumph. He'd done it! He'd rid himself of his greatest enemy and managed to maintain his "perfect record" at Big Ben in the process. "I'VE WON!" the mad rat began cackling from atop the hour hand as lightning flashed around him.
"On the contrary," an annoyingly-familiar voice came from below him. "The game's not over yet!" Looking down, Ratigan saw Basil hanging from his own blimp, holding a small object in his hand; closer inspection revealed it to be Felicia's bell. Ratigan briefly had time to wonder how Basil had removed it from his person before the detective started ringing it just as the actual bells inside of Big Ben started chiming ten.
At that moment, Ratigan inwardly cursed himself, remembering the number one rule he'd dictated towards his henchmen when committing the Big Ben Caper: Never be outside on the clock face whenever the chimes are about to ring; you'll never be able to resist falling from it due to the force of the vibrations. This unfortunately held true for the Professor as well, as he fell off the hour hand towards the blimp. In one final effort to bring Basil down with him, the larger rodent grabbed at the detective, tearing his arch-nemesis and the propeller apart from the blimp and joining Ratigan in their fall towards the Thames.
As the force of the fall began to eat away at Ratigan's consciousness, the Professor's last thought was an outright refusal to believe Basil had bested him at the site of his first great criminal triumph…