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After everything that has happened, the Doctor could not have been in worst condition. Everyone was gone. He left Rose in the parallel universe with his doppelganger, Martha, Jack, and Mickey had left him, Sarah Jane had a child to take care of, and Donna, he had to wipe her memory. What was worst is what the Ood said to him, it shakes around in his mind, "Your song is ending." He looked at the Tardis console.
"Where too next?" The Doctor pushed a button and then sparks flew everywhere and the ship was rattling non-stop and when it finally landed, everything seemed normal. He then grabbed his long-coat and sonic screwdriver and walked out the door. What he saw was London and yet… it looked like it was under some sort of totalitarian state. "This is wrong. The streets should be filled with people." Just then several tanks and military vehicles appeared and a bunch of soldiers with guns appeared.
"Hold it right there, scumbag!" One of the soldiers shouted. "Hands up!" The Doctor did as he said and secretly pulled out his sonic screwdriver. "We are relieving you of your… um… box."
"Why?"
"It just appeared out of thin air and scans are showing high levels of technology in there."
"Well, you're not wrong." The Doctor presses a button on his sonic screwdriver that slams shuts the Tardis doors. The Doctor puts his arms down. "You'll never get inside it. Definitely a parallel universe."
"Enough! I am taking you to the High Counsellor." The soldiers handcuff the Doctor and take away his sonic screwdriver.
A little while later in the Fortress of Solitude, the soldiers have finished escorting the Doctor. They see a man floating in mid air in a blue uniform with a red cape and an S-emblem on his chest. Next to him is a woman whom is wearing a sort of armor and carrying a lasso, sword and shield. They are revealed to be Superman and Wonder Woman. The soldiers throw the Doctor down at his feet. "This is the Londoner who was out after curfew," the soldier said, "He has in possession a sort of box that just appeared out of nowhere, and he had this." The soldier hands them the sonic screwdriver. Superman's eyes glow blue for a second and then return to normal.
"Two hearts." Superman said.
"What?" Wonder Woman asked.
"He has two hearts. Which means he is not of Earth." He nods at Diana who wraps her lasso of truth around him. "Who are you?"
"I'm the Doctor."
"Doctor? Doctor who?" Wonder Woman asked.
"I will not tell anyone that."
"The lasso compels you to tell!"
"NO!" Even with the lasso, the Doctor refused to tell his real name. This impressed both of them.
"No one has ever done that."
"Alright, Doctor. Where do you come from?"
"Gallifrey. I am part of a race called the Time Lords, I am the last of the Time Lords as they are gone."
"Who were the Time Lords?"
"Guardians of time and space. We were the first to invent time travel. My Tardis is the last of them. It can take you to any point in history, from beginning to end, and to anywhere in the universe simultaneously."
"How can one tiny box do that?" Diana asked.
"It's bigger on the inside. An artificial dimension crammed into what is now my ship."
"What happened to the Time Lords." The Doctor sighed for a moment.
"I had no other choice. There was a war, a war that concerned the whole of time and space. The Time Lords of Gallifrey vs the Daleks of Skaro. The Daleks are the most evil creatures in the universe with a sole goal of wiping out everything not Dalek. They mounted a full-scale assault on Gallifrey. If they succeeded, the Daleks will have achieved their ultimate goal and become the supreme beings of the universe. All the while the universe suffered around us. I came to conclusion there was only one way to end the suffering and the Daleks existence, destroy Gallifrey. I had no intention of surviving. I guess that's my punishment, I live with that regret every day. When I close my eyes, I can hear more screams than anyone can count. I wish there was another way." Superman grabs the Doctor by the throat.
"You killed your own species!"
"I had no other choice." Superman then lets go of the Doctor. "You know there is a way to make this interrogation go faster, when I headbutt people, I can show them what I have went through."
"Bad idea."
"Right, the guards did say you have invulnerability. What about this pill I have been hearing about?"
"What do you think, Diana?"
"He does have the lasso of truth wrapped around him."
"Fine." Superman hands the Doctor a pill, he swallows it, and then the Doctor headbutts Superman. Superman cries out in pain for a moment, as he can see every adventure the Doctor has been on, the people he met, the enemies he made, and every one of his incarnations. "I can… feel your pain, Doctor. I can see all of them… all of your… companions. Some of them have died, yes? Like this Adric fellow?"
The Doctor was forced to rethink that moment. "In my world, it wasn't a meteorite that crashed 65 million years ago, it was a human ship that fell through time. Adric stayed behind to save the rest of us. I tried to save him." What happened to Adric was one of the Doctor's most devastating memories, he even kept what remains of that star of his.
"How many more, Doctor? How many more people close to you got hurt or died because of you?" To rethink them... all of them… it was too much for the Doctor. "If what you have shown me is true, then you know pain better than anyone."
"Yes. And what is your story?"
"I had a wife, Lois Lane, she was pregnant, but a madman got a hold of her. He used a fear toxin to make me kill her, and at the same time, destroy Metropolis." He said all of this in a sad tone. "I avenged their deaths. I brought the man responsible to justice."
"How?"
"He was too dangerous to leave alive."
"You killed him?"
"I swore that it would never happen again, crime and war would be a thing of the past."
"So, you built a regime to do that?"
"Yes. And you, Doctor know pain better than anyone. You would be a great use to us." Superman extends his hand. "Join us."
"You took one life to save thousands."
"To save millions."
"But it wasn't just one was it? How many more? Who else's blood is on your hands?" Superman was silent for a minute, thinking back, Green Arrow, Hawkman, Gordon, many others.
"Are you in or out, Doctor?"
"I cannot be a part of what your doing. You know who I am, I don't like the idea of killing. I think I'll take my Tardis and sonic screwdriver and go."
"Very well, Doctor. But I thought you, of all people would understand." Superman hands the Doctor his sonic screwdriver.
"I do understand. That is why I cannot be a part of this. So, where is my Tardis?"
"It was taken to Lex's lab downstairs."
"Thanks." The Doctor walks downstairs. And sees a bald man coming out of his Tardis. "Hey, who are you?"
"Lex Luthor, who might you be?"
"The Doctor. And that is my Tardis. I thought I locked it, how did you get inside?"
"It wasn't easy. But then there is this special key I made, it is coated with nanoparticles to…"
"To fit in any keyhole."
"Exactly. And I must say, it is extraordinary. An artificial dimension crammed into a special containment unit."
"Or a Tardis. It stands for Time and Relative Dimensions in Space. The Tardis is a machine that can travel anywhere in my universe at any time in my universe. Speaking of which, she can only draw her energy from my universe, but we're not in that universe so where is she getting her power?"
"I charged one of the power cells with speed force energy, the speed force is a multiversal singularity that allows speedsters like my friend, Barry Allen, to travel through time by running faster than light and vibrate his molecules at different universal frequencies and allow him to travel to other universes. It is also how I brought you here."
"What?"
"Through the speed force, thank you Barry Allen, I found a way to see into other universes. I eventually came across your Tardis towing the Earth. Let me guess, you used a rift as a lasso?"
"Yes. But you just can't pull objects from one universe to another without both universes falling into the void."
"With the speed force, I did. All I did was vibrate you and the Tardis at a different universal frequency. Do you mind if we take this in there?" He asked pointing at the Tardis.
"Uh… sure." They both walked inside. "So, you managed to vibrate me and the Tardis here and that only creates minimal damage to both worlds, which they will be able to seal up. Lex Luthor, you are a genius. And I don't usually say that because of, well, me."
"Yeah, listen, I need your help. Superman, he has become a tyrant, I need your help to bring him down."
"What?"
"Superman used to be a good guy, a good man. Joker changed that. People have died because of his crusade, good, honest, innocent, people. People have protested against Superman's regime, but they all get arrested or worse. People critical of Superman's regime disappear, politicians, reporters and journalists, even heroes who stood against him. I fund the insurgency, but there is little we can do without help." The Doctor was silence for a minute. "This world needs a doctor. What do you say?" The Doctor nodded his head.
"I understand the pain Superman went through, but that doesn't give you the right to take innocent lives. I'm in." The Doctor shook Lex Luthor's hand.
"Now before you leave, you might want to think of some excuse to stay here to say to Superman."
"Well this is an old excuse." The Doctor reaches under the console and picks up a cylinder device. "I'll just tell him I need a new fluid link and your lab does not have the necessary materials for one." The Doctor and Lex Luthor walk out of the Tardis.