Disclaimer: I do not own LOTR I am just borrowing the characters temporarily.
In horror the Alliance of Light watched as Aragorn and Frodo were dragged to the front of the parapet by two nazgul each. Frodo appeared pale and lost, the young hobbit had been visibly beaten and his head hung listlessly. Compared to Aragorn though he appeared almost healthy. Isulder's heir was covered in bruises, his clothes torn indeed almost shredded off in places and he was being dragged as though he was unable to use his legs as support. But unlike Frodo he was not in despair, or at least not visibly. He held his head up and his inner fire still burned brightly. His eyes swept across the assembled forces and Arwen could almost feel will's strengthening as backs straightened in answer to the future king's unspoken command. As his eyes touched on her she felt his love wash over her. Renewed strength of purpose filled her.
Sauron stepped forward, between and one step in front of his two prize prisoners. "Kneel before me and I will allow these two spies to live."
No one moved or spoke.
Without turning Sauron lashed out with his arm. Aragorn rocked back with the force of the blow and his two imprisoning nazgul had to tighten their grip so he did not fall. Lifting his head Aragorn blinked twice to clear his vision and met Sauron's eyes unflinchingly, refusing to back down when the Dark Lord turned to glance at him. "You will learn," Sauron hissed, again striking out at Isildur's heir with an even more forceful blow. This time Aragorn's body curled up on itself in an instant, automatic reaction as the nazgul lost their grip. Still, he managed to turn slightly as he fell to land on his side rather than on his knees before the Dark Lord. He lay unmoving where he landed and Frodo did not react at all as he stood unmoving between his nazgul guards who were watching the drama unfold intently. Sauron turned back to his foes. "He will die a slow and painful death in front of you," he vowed ominously. "But first, witness the power of the One Ring."
Horror struck Arwen, she could not move as she watched as Sauron lifted his hand to display the circlet of gold that signaled the downfall of Middle-Earth. Suddenly a small, dark blur grabbed the ring before the Dark Lord could slide it on his finger and rolled to the ground. As the nazgul grabbed for the hobbit she was aware of Legolas stiffening beside her as Halbarad did the same in front of her. Her gaze shot to Aragorn, who had managed to push himself to a sitting position. "Estel," she breathed in horrified knowledge just as her love's voice cried out, "Frodo!"
The hobbit did not hesitate to turn and toss the ring to his guide and protector.
With a shudder of disgust Aragorn caught the ring and slid it on his own finger. Those watching were never able to describe in detail what happened next. A dark light seemed to flash across the world as the future king, his hand raised for all to see that the ring now glowed with words hidden since the end of the second age, dragged himself to his feet. For an endless moment no one moved as Isulder's heir stood with his head bowed and hand upraised. Isulder's bane had accepted a new master. As horrified recognition of the necessity of this sacrifice filled the leaders of the Alliance of Light the new Lord of Rings remained unmoving with his head bowed, but strength seemed to emanate from him as did a feeling of great power in use.
"You will pay for that, human!" the Dark Lord spat, looking to his nazgul.
At those words Aragorn at last raised his head to meet Sauron's gaze. Despite the gasps and mutterings around her Arwen could not tear her eyes from the man she loved. "You are no longer master of the One Ring," he answered in a calm and controlled voice. "I control the nazgul."
In a rage the Dark Lord drew his pike and charged.
Neatly sidestepping Aragorn grabbed Anduril from the obliging former Witchking of Angmar and raised it, neatly taking off Sauron's head. Power roared out, knocking Arwen to the ground. When the force had passed over she pushed herself up, seeking Aragorn. He was standing in the same spot, staring out into the distance, Frodo at his side looking up at him with concern. A small part of her wondered if he had really been so broken. But most of her attention was focused on the man next to him. Her loving eyes saw the pain and exhaustion he was fairly successfully hiding. As she watched he turned to the nazgul and held out his hand. "Give me your rings." With manifest reluctance all nine did. Another rush of power, not nearly as strong, brushed by them. Nine black robes drifted the ground, empty.
With calm deliberation he turned to face the allied forces of good. His eyes swept the gathered army. "It is over." Soundlessly he collapsed and lay still.
As she raced with Legolas, Halbarad, Gandalf, her brothers and father to her betrothed's side Arwen Undomiel knew with horrified certainty that it was not over. A new horror had begun and she did not know if any of them would be strong enough to stop it.
Above them the Lord of the Rings did not move, the ring bearer slumped beside him. On his hand the ring glowed brightly.