So ummm I would have posted this last night but the lovely website decided that it didn't want to upload my document so here it is now. I enjoyed writing this one for some reason, once again, it's a bit angsty. But it's 10, what can you expect? He kinda has a lot of internal angst he works through. And sadly, I don't actually own Doctor Who. So many things would be different if I did. Don't even get me started...

Title: Of the darkest memories

Summary: The Doctor has seen so many things in his life. Donna finds out what the most painful for him was.

On days that the TARDIS wasn't working Donna liked to wander down the long, intertwining corridors. She could only spend so much time cooped up in the control room and listening to the Doctor mutter and grumble under his breath about a bunch of techno-babble she didn't understand. After a while, she simply got bored. It was days like this she liked to find new rooms in the TARDIS that she had never seen before.

In the past she found a library that would put Alexandria to shame, an Olympic sized swimming pool, a spa room of some sort, a gym, three gardens, half a dozen fully stocked kitchens, telly rooms, and games rooms. Donna had a feeling that she had only hit the tip of the iceberg. She never looked for anything in particular; she just wandered until a door caught her attention. Some of them were marked with small crème colored plaques. Each plaque had a series of symbols on each. It didn't take a rocket scientist to figure out that it was Gallifreyan.

Today Donna took a series of two right hand turns, three lefts, and another right. It brought her to a hallway that she had yet to go down before. "Well, let's find out what's behind door number one," she said to herself. On her left was a blue door—which wasn't surprising since all the doors were blue on this ship—that was unmarked. Next to the door was a hand scanner. It didn't take Donna long to learn that's how all the doors opened in this ship. Apparently opening a door with a knob was beneath the Time Lords.

Sometimes Donna came up to a locked door, but this particular one opened up as soon as Donna placed her hand to the scanner. It opened silently, but as Donna looked inside she couldn't see anything but blackness.

With her curiosity getting the best of her, she crossed the doorway and the room lit up like a football pitch. The entire room was washed out in blinding white light—the floor, the walls, the ceiling, all of it. In the center of the room was a single white chair.

"What the hell is this?" Donna asked herself and she stood behind the white chair. It didn't look particularly dangerous, so she sat down. As she did the wall before the chair literally opened up to reveal some sort of screen. There was a sputtering sound and the screen came to life.

Words couldn't begin to explain the things that Donna saw on that screen. There were planets and ships, and all of them were burning. The spaceships blew each other of the skies as the ground far below them was engulfed in flames.

"I-I don't want to see anymore!" Donna cried out. The screen changed again, but this image wasn't any better than the one before. It was another spaceship, minding its own business when out of nowhere it exploded and broke into thousands of pieces. The images came, one after another-something burning, something exploding, someone in pain. It was more than Donna could stand, but yet, she was unable to pull her eyes away from that screen.

When she thought she was going to be sick from seeing these images, the screen shut off completely. "How did you find this room?" a voice behind her asked. Spinning around Donna saw the Doctor leaning in the doorway, his face ashen.

"I was just walking around and picked a random door. I don't even know what I did, I just sat down. What is this room Doctor?" Donna asked as she got out of the chair.

"A memory room. When you're as old as me, and have seen as many things as I have you need a place to keep some of those memories. The question is, how did you get in here? The TARDIS is supposed to keep anyone but me away from this hall." He stepped up to a wall and held his hand to it. It was as if he was feeling for something.

"Maybe the TARDIS wanted me to see this room," Donna suggested.

"Perhaps…"

"Those images on the screen, those were things that you've seen? Things you remember?"

"Yes. So many things I wish I could forget…" the Doctor didn't seem to be talking to Donna at this point. It was more like he was talking to himself. "But you know," he added, turning to Donna. "Not all of them are bad memories." The Doctor shut his eyes, obviously thinking about something. With another sputter, the screen came back to life and Donna saw the three faces fill it up. Two men and a woman. One of the men was telling a story while the others all laughed. At one point the young woman looked straight into what must have been the Doctor's eyes. Donna could see the sparkle of life in them. She grinned and stuck her tongue out between her teeth. The image faded, but it was soon replaced by another one and the same woman was in it. Memory after memory played, and she was in all of them. She was always smiling, always had that sparkle in her eyes.

Soon the screen faded and Donna turned back to the Doctor. He looked at the screen, the saddest of smiles etched upon his lips. "Who was that? That woman," Donna asked.

"That was Rose."

"She looked so happy. She was always smiling."

"She was happy. So happy that it poured out of her. She put happiness back in me. After everything I had seen, she was the one that showed me how to be happy again. But, she's not here anymore. I've had to get along without her." Donna opened her mouth to ask the Doctor more about Rose, about what had exactly happened to her. Before she had the chance to, he was gone. With the little bit she knew, Donna knew remembering Rose still hurt him. She just wanted to know how he lost her.

Behind her, the screen came to life for a third time. Donna watched as Rose held onto some sort of lever. She was floating in the air, with a weakening grip. She couldn't hold on any longer, and she slipped. Donna watched as Rose spiraled away from the Doctor, towards a blinding white light. Then a man appeared out of nowhere. He caught Rose, and for the briefest second, her brown eyes looked into his and then she was gone.

Donna had never seen that look in someone's eyes before. Her eyes didn't hold the happy sparkle they had in all the other memories. The look in her eyes screamed 'I'm sorry'. Then, she was gone. The screen went out after that. Donna stood there, shocked by what she had seen. In her gut she had a strong feeling that out of all the terrible things that Doctor had seen, watching her vanish had to be the worst.