The Doctor felt like he was losing his mind. Oh, he did a brilliant job of holding himself together when Rose was around. But, then again, he didn't have much of a choice, did he? He just couldn't let her find out that he had, not only ruined the tank for the TARDIS, but also that he didn't seem to be able to focus on anything. Anytime he tried to talk to her, mess with his sonic screwdriver, or take a look at the TARDIS coral, his thoughts were drowned out by strange things. He heard Davros shouting out orders during the Time War; heard his own people screaming. Things the Master had said to him came thundering into his mind like he was having post traumatic stress disorder flashbacks.
He had locked himself in the bedroom to keep away from her. She couldn't see him like this.
After dozing off in a chair by the TARDIS coral for a little while, he shot awake with a thought.
It is all connected, he thought. Jumping back in time, the disappearances of the staff, his mental breakdown, the Time Lord Doctor, Dr. O'Brien… it just had to be all connected. But how?
C'mon, he told himself. I am, in no uncertain terms, a genius. I should be able to piece all of this together.
Exterminate!
He pushed that out of his mind. It's not real, he thought.
The Doctor pinched the bridge of his nose and tried to focus. Then, he heard Donna's voice.
Reconfigure the algorithms, Spaceman! It's not that hard. Refasten the current bolts. Get some readings on the quantum molecular structure. Make sure the nucleus of the molecules are positively charged. Manage the electric displacement field…This wire here…Sonic the fission-producing neutrons…
Wait! Something screamed in the back of his mind. No! Stop!
He dropped the sonic screwdriver and shoved his glasses from his face. Had he really almost done that?
"You've got to be kidding?" he said softly, in shock.
The Doctor had not been repairing the TARDIS tank. He had just been blindly following the voice in his head – because it had been a voice that he trusted -Donna's voice. But he doubted that Donna would have wanted him to turn the TARDIS coral and tank into a nuclear bomb.
Dragging his hand down over his face, he let out a shaky breath.
"Blimey," he whispered to the empty room. "That was a close one. What the hell is going on?"
I need to sleep, he thought. That's it. I just need sleep. Rose is always telling me that I don't get enough now that I'm human. I'll feel better when I get some sleep…
He rubbed the back of his neck and stared at the tank before shaking his head and leaving the room to brush his teeth.
I'm going mad and almost destroyed us all, but here I am now worrying about cavities. Being a human is so strange.
As he stared at himself in the mirror, working the toothbrush around in his mouth, the Doctor had a moment of perfect clarity.
Dr. O'Brien's office…the case files. If I can get a look at those case files from the couples that were here last month, then maybe…just maybe, I can find a link. It is all connected. And all those little lines are leading straight to Dr. O'Brien.
When the Doctor left the bathroom, about to set out on his new mission, he saw Rose standing in the doorway to the bedroom. She was gaping at the ruined mess of the TARDIS tank. He tried to say something to diffuse the situation, but he was at a loss for words and his mouth snapped shut.
"Doctor, what happened in here?" she asked him, her blonde hair framing her wide, terrified eyes.
He cleared his throat, shoved his hands in his pockets, and rocked back on his heels nonchalantly. "Oh, just…doing some repairs," he lied, running his tongue along the inside of his cheek out of nervousness.
"You've completely undone everything!" she exclaimed, concern coloring her voice.
Of course she'd see right through it; she wasn't stupid.
"Nah. She's fine. It's all fine. Don't you worry, Rose Tyler, I'll have everything ship shape soon. Try saying that five times fast."
"Don't make jokes," she said, becoming angry now. "Doctor, what's gotten into you?"
"Nothing," he snapped. "I'm fine. Told you…it's all fine. I'm just gonna pop down to the shop. Need anything?"
"I don't think you should be goin' anywhere," she told him, shaking her head.
"Nine hundred years of going wherever I please. That's not going to change now," he said with a stern tone and started walking towards the door.
"So you just leave whenever you want?" she asked him.
"Yup," he said, not turning around.
"Then what makes you any different than him?" she shot back at him.
The Doctor left the cabin and stomped out on to the dirt road. Why would she say that to him? Of all the cruel things that she could say…
He was so angry…so angry he could hit something. Then, he stopped. Why had he thought that? He knew himself well enough now to know that he wasn't an angry person or a violent person…not in this form anyway. So why had that thought crossed his mind?
Something is really not right, he thought to himself as he continued to make his way to Dr. O'Brien's office.
He passed by dimly lit cabins and all the way, he could hear the couples inside. They were all arguing.
"You never listen!"
"I should have left you years ago!"
"My father was right about you!"
"You always hated that I work!"
"You're terrible, you are! I hate you!"
The Doctor's eyes darted around the resort. What the bloody hell was going on?