For a moment, Donna felt nothing but sadness and confusion. With that one word, she remembered everything. She remembered the TARDIS, all the new planets they visited, and the enemies she and the Doctor had faced.

But most of all she remembered that she had forgotten all of it. He had dumped her back on Earth and, apparently, moved on.

That git!

Donna immediately ran after the trio, shouting, "Oi! Doctor! You get back here!"

When she got near enough, Donna saw the two new companions stop, but the Doctor stubbornly kept walking, almost marching in the attempt to get away from her.

Oh no you don't, Donna thought determinedly. "Spaceman!" she yelled loudly, still running after him. "I wanna talk to you." She finally caught up to him and grabbed him by the shoulder, stopping him in her steel grip.

Donna forcibly turned him around and looked into green eyes that were so different now, but at the same time they were the same as when she traveled with him.

"It is you." Donna whispered. It was unbelievable. How could she have forgotten? Why had she forgotten?

There was a pause. The Doctor opened his mouth, but Donna beat him to it:

"You left me, you jerk!" She screamed, slapping him across the face, but not that hard; however mad she was, she was still happy to see him.

The Doctor immediately held up his hands to defend himself and said, "I'm sorry, Donna, I had to!" He saw the Ponds walking over to them, confused looks on their faces, but they also seemed amused at the spectacle.

"Doctor," Amy managed to say between laughs, "Who is this?"

Donna stepped back from the Doctor and replied, "Donna Noble, I used to travel with the Doctor." She hit him again on the arm, "Until the git left me!" She held out her hand and they all shook hands.

"Well, I'm Amy Pond, and this is is my husband, Rory. Nice to meet you."

"Likewise," Donna replied. They seem like nice people, she thought.

The Doctor, rubbing his arm, walked over to Donna. He took her hand and led her away from the Ponds back to the TARDIS. "Go see the sights guys. Be back at the TARDIS in an a hour."

The Ponds nodded and walked away. Once they were finally alone, the Doctor turned to Donna. "I'm sorry, Donna, I truly am-"

"How could you, Doctor?" Donna asked, gripping his hand in hers. "I was going to travel with you forever, but you left me."

"Donna, do you remember when you absorbed all my knowledge, back on on the Dalek ship?"

Donna laughed. "Of course I do. I did in fact save the world with it."

"But do you remember what I told you after we left Rose and my double in the other dimension?" He asked this with a slight tremor in his voice, like he didn't want to say it.

Donna shook her head, because she really didn't. She remembered leaving the alternate dimension, entering the TARDIS, and the Doctor apologizing, but then nothing.

The Doctor sighed. "Donna, when you absorbed all that knowledge, it was too much for your brain to handle. It was starting to burn it up already, and the only way I could save you was by making you forget that you had ever traveled with me."

"But I remember it, Doctor!" Donna protested. "I remember everything we did together: Pompeii, Agatha Christie, the Daleks! And I'm fine!" She gripped the lapel of his tweed jacket and brought him closer, wanting him to understand. "You didn't have to make me leave. You could've just blocked off all that Time Lord information from me or something."

"Donna, please, you don't understand-"

"You're bloody right I don't understand!" She felt a lump in her throat grow and she forced it back down. She wouldn't break out into tears in front of the Doctor. Donna wasn't even sad, or even angry, just confused.

"You left me. Erased my memory and walked out on me," she whispered. "You were my best friend, and I didn't even remember you. I didn't even get to say goodbye."

Donna caught a glimpse of regret in the Doctor's eyes, and she realized that he was sad about that too.

"You were my best friend, Donna."

The words were spoken so softly, Donna was sure that she hadn't heard him correctly.

"What?" She asked quietly.

The Doctor looked up and pulled her close. He gently pressed his lips to hers, holding Donna in a hug.

It was a soft, friendly, reassuring kiss. It was a kiss between best friends.

Donna pulled away first, but kept hugging him, resting her chin on his shoulder. That nagging feeling that she was missing something was now completely gone.

"I just wanted a mate, Donna," the Doctor murmured, both of them holding onto the other with everything they had. "And you were the best, you were brilliant."

Donna's heart skipped a beat at the compliment. "You weren't too bad yourself," she murmured, laughing a little. She could tell that this meeting was coming to end, and for some reason, she felt alright with that.

The Doctor smiled. "That's the Donna I know." He pulled away from her, both of them laughing at the tears in the other's eyes.

"You take care of yourself, alright Doctor?" Donna wiped the tears out of her eyes. "And you make sure that those friends of yours stay safe."

"If you want," the Doctor offered with a muschievous smile, "You could come with us. Donna Noble in the TARDIS once again?" He patted the blue box affectionately, a hopeful look in his eyes.

Donna shook her head. "I'm sorry, Doctor, but I can't." Donna wished she didn't have to see the hurt look in the Doctor's eyes, but this was how it was supposed to be. It hurt, but she had moved on, and so had he.

"I'm married now, and you've got the Ponds," she clarified. "I have to move on, Doctor." Donna looked at her watch. "And now I have to think of a reason as to why I'm late for a job interview," she sighed.

The Doctor looked up and his features brightened. "Well," he said happily, looking back at the TARDIS. "I do have a time machine, I suppose I could give my best mate a quick trip to make it to a job interview." He unlocked the doors and opened them, stepping aside to let her in.

"Oh, you are brilliant." Donna laughed, going through the doors.