"The Medusa Cascade."
The TARDIS spins to a halt, swimming in the glitter galacticum that is the rift of time and space, where there is nothing and everything. She floats among the stardust, catching in the winds unbound by gravity.
"A rift," the Doctor begins with heavy hearts, "in time and space. I came here when I was young, actually, only 90 years old."
"This is amazing," John gasps at the view he can only see through the monitor. It's a sea of colors to his human eyes. "Doctor, what's here?"
"A metacrisis," she sighs. Her hands are in her pockets. Her eyes look dull, tired with ashen complexion. "The Medusa Cascade is a rift, a pivotal point in time and space, across dimensions and realities. This is from where the time ripples originate. Somewhere, in another reality, the Medusa Cascade is hosting a horrible degradation of the laws of reality. Holes are being ripped through universes, including ours, probably the result of a dimension canon, literally destabilizing every universe it passes through."
"But how can something do that much damage?" John asks as he drags his tired body to where the Doctor stands. "And how can it rip through our reality?"
"John, when you met Lee, he told you realities were bending around you, and that the Doctor had died. Reality is fixing around a point, and that point is you." The Doctor pulls out two gold rings from her coat pocket. Along with them, she pulls out the Sonic, with major modifications.
"What have you done to the Sonic?" John demands at the sight of it.
"Screwdriver: it'll be much more useful," she tosses it to him. "You keep that safe, with you, at all times form now on."
"Doctor, tell me what's going on," John clenches the Sonic (Screwdriver?) tightly in his fist. He sees the gold rings in her hand. "Why do you need with the biodampener?"
"This one is for you." The Doctor holds the ring up to their eyes for just a moment before slipping it on his finger. She keeps a hold of the hand, for all that she's worth, with tears in her eyes. "Keep it with you, John, it's very important that you never let this leave your hand again."
"Why do you have two of them?"
"This one is from another dimension," the Doctor rushes with hardly an explanation. "It stays with me and the one I gave you stays on your hand."
"Doctor, please," John begs of her with a whispered tone, "just tell me what's going on. Tell me what's happening."
The Doctor bites her lip. She told herself she wouldn't cry, mostly because every time she cries John tries to comfort her, and it melts her hearts. She can't let that happen this time, because this is the end. The day of the Doctor has arrived. "This is goodbye, Earthboy."
John's heart stutters over the words. His eyes turn cold and beads of cold sweat collect around his brow. His throat feels like he's being suffocated. "Doctor, I don't understand."
"John, our reality is breaking down. The world is wrong, but I am going to fix it." The Time Lady has fire in her hearts, spitting sparks onto her tongue. "I am going to restabilize the reality nexus by going into the void to cross the transdimensional timelines of the bifixed metacrises."
"You're…you'll kill yourself," John whispers just to make himself understand what's really happening. "You can't—you're talking about erasing your existence for this world!"
"I am the Doctor!" she snaps in his face. Her voice booms and echoes in absolute surety. "I am the Doctor, the protector of this Earth—any Earth, and right now, the depths of the Medusa Cascade is where the Earth happens to be!"
"What?"
"Nothing!—now, remember that reality is going to bend around you. Stay in the TARDIS, she has shields that should protect you as you're being pulled through universes. Stay here, keep the biodampener on, keep safe." The Doctor heads for the door but John grasps the handle tight. He keeps the door shut with a grave look on his face. "John, you need to let me do this."
"You promised me forever," he says shortly.
"I know, and I am sorry, but you have to let me do this," the Doctor looks from the door to John's darkened eyes, "you have to let me save you!"
"Not this time I don't!" John shouts and bangs his fist on the door. The sound, the ruckus, doesn't bother her in the slightest. "You can't save everyone, not this time!—not today!"
"But today is it! This is my only chance, John, and if I don't do this then this whole universe and God knows how many others are destroyed! This is our only chance, and I am it! I am the only hope this world has for even a chance of surviving!"
The air settles in the doorway of the TARDIS, weighing on them. Their eyes are fighting a violent battle of wills. John's hand remains flat on the wood of the door while the Doctor's hand grasps his fingers, willing his to respond like they normally do. Her fingers continue to tighten around his until finally his curl around hers as well.
"Why is it always you?" John asks rhetorically.
"I don't know if it is, actually," she chokes on a poor example of a laugh.
"Please don't do this," John whispers, but knows it's selfish. This is the life of the Doctor: saving worlds, rescuing civilizations, not being able to save everyone but still trying to save someone. This is what it means to let people live without you, move on, forget you, so that they can be happy. "Please don't leave me."
The Doctor leans up and kisses John's lips with a loving delicacy. It at least forces some silence upon them both. When she pulls away he has tears running down his cheeks, onto his lips. She can lick hers and taste the saltiness. Her thumbs wipe the tears away, leaving only a slight glistening against his freckled skin. "You're one of a kind, John Smith."
"And I love you for it."
John feels the Doctor's lips fade from his as the doors open and she drifts out. He catches just a glimpse of her red hair, flying out behind her as she delves into the Medusa Cascade, all swirling color and sparkling light. The doors close on him and he feels like he's having a heart attack.
Hold on, Earthboy.
"What's happening?!" John's shouts bounce off the ceiling. Spit bubbles at the corners of his mouth where he clenches his teeth. "Tell me what's happening!"
It's the metacrisis. You're going to feel the effects of it because you're a pivotal point in time just as much as our Doctor is. You are one of the children of time.
"What's happening to my heart?!" John spits as his entire chest burns up.
I can't tell you that yet, John, but if you want to save the Doctor you must do as I say.
"Okay!—okay, I'm listening! Just tell me what to do! Tell me how to save her!" John clutches at his chest but forces himself upright and to the TARDIS console.
The Doctor is tying different realities together to create one big paradoxal alternate universe around which reality can bend, with you safe in it. Your only chance is to follow her into the void, with the biodampener, and the Sonic Screwdriver to hone in on her signal. You are half a metacrisis, John Smith, and the Doctor is the other half. You are one of a kind, because you're a human-Time Lord tri-dimensional metacrisis.
"What does that mean?!" John grips the edge of the console as another wave of white hot pain bursts inside his chest. "What's happening to me?!"
A ripple across different realities, bouncing back and converging on you. You're growing a second heart.
"Like the Doctor?" John gets a moment of relief to look up.
Yes, now listen to me, Earthboy. Take the Psychic Paper.
"All right," he grabs at it and stuffs it in his pinstripe jacket. When did he put this bloody thing on again?
I am going to launch you straight to the point where the realities converge within the Medusa Cascade, in the same way a vortex manipulator would.
"Okay, so I can get to the Doctor," John grabs the trench the old girl popped up for him on the railing. He slides it on in jerky motions.
Once you find her, you have to be willing to make a great sacrifice, John Smith.
"Whatever it is, I can do it!" he shouts through his teeth, clenched tighter and tighter.
You must be willing to kill the Doctor as we know her.
This stops John entirely, from all motion and thought. "Tell me you didn't just suggest that."
This Doctor's time has come to an end, John, and the only hope of saving any part of her is for you to take her place in the reality nexus and rewrite her into the new dimensional matrix in your place.
"As…a human?"
As a human, John; our Doctor has to surrender her timeline to one who can stabilize the reality that could destroy her.
"It's me, isn't it? It's me; reality bends around me." John's face has turned dark, murderous, as he looks up to the disembodied voice that circles around his head. "You're asking me to take the Doctor's unraveling timeline and take her place so she can replace me in mine. Then, what?—we bind together realities from there?"
Yes, essentially, if you take the correct timeline and bind it to our reality while in the Medusa Cascade, reality can rewrite itself around you. It is the only chance this world has.
"Why wouldn't the Doctor tell me this?"
…There is a chance you could be unwritten when you try to cross the misaligned timelines within an unstable dimensional nexus.
"I could disappear, then the Doctor is doomed either way," John clenches his fist. He both loves and loathes the feeling of cold, solid metal on his ring finger. "But you're letting me try."
Time Lords can see all of time and space, until it is set off balance. The Doctor has lost sight of her future, and that's why she has gone to correct the imbalance herself. She thinks the choice is hers to make.
"She's trying to protect me," John grumbles, reluctant to admit her reasoning. "It's still not right!"
Then go after her.
"What about you?" John deposits the Sonic Screwdriver into the trench's inside pocket.
Keep the Sonic Screwdriver with you. It is of my make, and connected to my technology, whether in this reality or the next. So long as you have that, you can find me.
"Is that why the Doctor gave me the biodampener?" John approaches the door slowly.
It is.
"She said the Earth was in the Medusa Cascade. She could have only gotten this from Gramps."
Your Earth has already been torn through realities. She has gone to in search of it, and your family.
"She'll take care of them," John states less than asks. He is still headed for the doors, slowly enough.
I know this is not the eternity you had in mind, John Smith, but this is the only hope for any lasting reality to exist. Are you willing? Are you capable of shouldering the burden of a Time Lord? Can you take a thousand years of knowledge and harness it on as your own? Do you want to find Donna?
"I am, I will," John takes hold of the door handles and takes in another breath, "I do."
John Smith, human of London, hurtles from the safety of the TARDIS. He flies through space and into the light that is the rift. It's white, blinding, swallowing his insignificant little existence and enveloping it with time and space.
John?
Doctor, I'm here to help! John squints against the light. He can't see anything.
You can't!—I told you to stay in the TARDIS! It's not safe here!
John opens his eyes a little more and manages to see a silhouette. You're not the only one allowed to risk their lives, you know!
You're not a superhero, Earthboy, you don't know what could happen!
Every superhero has a reason for fighting, Doctor! John opens his eyes and braces himself against the rush of reality, rushing against his physical form. He reaches out a hand and finds the silhouette. He knows the fingers that curl around his, and he feels the clash of metal against his biodampener. And you're mine! You're my reason!
Existence rushes around them, time flowing like a river. It is all white, and blank, everything and nothing. Worlds are shifting and forming around them.
I'll take care of them! The Doctor's voice call to John as he feels her being ripped from him in the wind and the stardust around them.
"I'll find you!" John shouts to her as she fades once again. He refuses to lose her again. He waits, through the falsified passage of time. A thousand years of life pass by his eyes as a life now unlived but remembered. "I promise you I'll find you!"
I understand, now. My name is John Smith, I am a human, born on Earth. I traveled with the Doctor, an alien from the planet Gallifrey and a Time Lady. She can see time and space, and now, so can I. I have manipulated time and existence around me to save realities. I am a human Time Lord—a metacrisis. I am the Time Lord victorious, and I will save the Doctor, turned human. I am a Time Lord; I am the Doctor, now. I am the Doctor, and I have waited a thousand years to find the love of my life: Donna Noble.
—
"Donna, what are you waiting for?!"
Donna rolls her eyes as her mother's voice pierces her ears, even from the other room. Sometimes Donna really doesn't know why she puts up with her blasted mother, but something keeps her there. She never moved out, never went off on her own. Part of her told her it was just to make sure Gramps was all right, but she still loves her mother, in some weird way.
The ring on Donna's finger fits like it's made for her. It's a simple band of gold, obviously a wedding ring, but there's something special about this. It doesn't register as metal, doesn't set off metal detectors, doesn't heat up on contact, and doesn't fit anyone but Donna. The one time she let her friend Alice so much as hold it, the ring's surface burned her. The mark didn't last, and the pain faded quickly, but only Donna can wear it. She has had it for as long as she can remember, and now, she finally gets to wear it.
"Donna, you don't want to be late for your own wedding!" Sylvia pounds on the door.
Donna rolls her eyes. Sometimes she can't even remember why she agreed to marry Lance in the first place. She finds she often can't remember why things in her life are the way they are. The questions are plentiful, the gaps are huge, but she never bothered to protest to any of it. Some part of her, in instinct, just trusts that things are the way they are for a reason.
"Oh, you do look lovely."
Donna turns, startled by the sudden appearance of the new voice. By the door there leans a man in a pinstripe suit. He's skinny, with a long trench coat back dropping him. His hair is wild, like he's been sucked through a vacuum. His eyes are brown, darkened by time and life. He looks at her like he's expecting something. "Who the hell are you?"
"Hello," he smiles at her (rather dashingly) "I'm the Doctor."
"The Doctor?" Donna looks dubious, "that's your name?"
"In a way, yes," the man nods back and forth. "I have been looking for you for a long time, Donna Noble."
"Me?" she frowns at the stranger. "Why would you be looking for me?"
"That's kind of a long story. If you have something else to be doing," the man eyes her up and down. "I could always come back later."
"No, don't leave," Donna rushes out with a kind of urgency in her. The Doctor's eyes rake up her form appreciatively and she blushes at herself.
"I won't leave, Donna," he assures her serious as anything, "I promise you, I won't leave."
"Just," Donna contemplates, "tell me why you've been looking for me."
"I could show you," the Doctor tips up his chin and extends his hand, wiggling his fingers enticingly. "What do you say?—come with me?"
Donna stares at the man in awe. He can't be serious; just go with him, just like that? How the hell does he live his life?
"Donna, get down here!"
The Doctor's face becomes soft, almost reminiscent. "That your mum?"
"Yeah, she can be a real nightmare sometimes," Donna rolls her eyes nervously. Her heart is pounding wildly and she can't fathom why.
"Yeah, but it takes devotion to put up with family like that," the Doctor comes a little closer, with his hands in his pockets, "you must be a dedicated soul."
"What are you on about, Spacecase?" Donna raises a brow at him.
"I'm not a space case!" he pouts at her (rather cutely). "I think I'm more of a-a…a Spaceman!"
"Whatever you want to be, be it without me, I'm getting married!" Donna waves her hand irritably at him.
"Yeah, caught on to that bit," the Doctor murmurs unhappily. He sighs and bores his eyes into Donna blue ones. "Tell me you'd rather get married than find out why I've been looking for you and I'll leave, right now. I'll return the second you call me, but only if you can look me in the eyes and tell me you'd rather get married than come with me."
Donna stares at the stranger with mixed feelings. Her lips are slightly parted. She tries to keep her eyes on the Doctor's anticipatory face but they keep drifting down to his extended hand. On his finger sits a ring that looks identical to hers. It's gold looking, but she can just…tell…it's not a wedding ring, no more than hers is. For a reason completely beyond her her hand drifts towards his. Her fingers touch his and she finds his skin just slightly cool. Her eyes go back to his and he looks so elated by the feeling of her hand in his she turns pink in the cheeks. His fingers clasp around hers and she tries not to feel the implications of that. "Okay, fine, you get once chance…Spaceman."
The Doctor smiles at Donna: "allons-y."