They entered the Tardis. The Doctor was looking at a screen. Ava grinned, looking around.
"Hello my love. Did you miss me?" At first they assumed she was talking to the Doctor, until the Tardis made a noise.
"Doctor, what was that?" Amy asked alarmed.
The Doctor paused. "I think that was the Tardis."
Ava grinned running up to the console, twirling around. "She missed me!"
The Doctor frowned to himself. The Tardis shouldn't have done that. There was no way she could have faked that. It was definitely the Tardis that made the noise. There was no rigging that. He looked at the woman, who was currently stroking the console, much as the Doctor himself had done various times in the past.
Ava grinned and walked around the console, letting her hand jump lightly from each lever, switch and button. After she had done a 360, she looked at the Doctor. "So where are we going?"
"Nowhere…yet." He looked back at the screen, which had started a DNA test. She walked behind him. She chuckled at him.
"So much for proof. Ah well, I'd probably do the same thing." Then she paused, thinking. "I… Hey! I'm back. I can finally change out of these clothes. And have a shower! If anyone needs me, I'll be in my room!" With that she turned and ran off.
"Wait…What?" the Doctor asked. He turned to his companions. "You three, watch the screen. Tell me the instance it finishes." Then he followed the girl. He found her in a room only a few away from his own. He blinked as he looked around. He had never been in that room before, yet it was equipped with a bed and was full of souvenirs. Ava lay sprawled on the bed. She moaned slightly.
"It has been so long," she said without opening her eyes, "since I have slept. Or eaten. Or taken a shower."
The Doctor walked over to her, and sat next to her. She reluctantly opened her eyes and sat up.
"How are you doing this?" he asked.
"Why don't you tell me?" she replied.
He considered. "You might come from a species even more advanced than the Time Lords. But if so…"
"Why would I be here?" Ava finished. "If I was this supposed Super Race with the power to control the Tardis, why would I come here? If I wanted the Tardis, I could've taken it. If I wanted you dead, I could've shot you. And then there's River."
The Doctor nodded. "She believes you."
"Mmm." She lay back. "Quite the conundrum. Tell me if you figure it out." Then she groaned. "Right. I'm going to have a shower… If that's okay with you. Unless you'd prefer to wait for the results to come back. In that case, we should probably head back."
The Doctor thought about it. He was reluctant to let her out of his sight, especially if she was a spy. He looked around as he thought. A picture on the bedside table caught his eye. He picked it up.
"What's this?" he asked.
She sat up, and looked at it over his shoulder. "It's us. Paris. Outside the Louvre. 2018, I think. We had dinner remember? It was just after Leela, but before Romana. It was very fun. We got sketches done as well. Then we went to the Eiffel Tower. Poor K9 had to wait for us." She smiled fondly.
The Doctor stared at the picture. It was him. He would recognise that coat and scarf anywhere. He had his arms around Ava. They were both grinning at some unknown joke. In this photo Ava was wearing a red dress with black leggings. Her hair fell around her shoulders in waves. The Doctor ran his fingers over the picture. Could it be true? He wondered. If she was…what could it mean? He wasn't alone? That he wasn't the last of his species? How would that affect him? Would he be happier?
Ava watched him. She could almost see his thoughts. He was starting to believe her. She smiled. Oh how I've missed you Doctor.
She stayed silent. Waiting. Hoping.
There was a knock at the door. They jumped startled.
"Umm, yeah." Rory said. "River says the test is almost done. She said I should get you." He looked slightly embarrassed to have interrupted them. Ava gave him a charming smile.
"Finally!" she rolled off the bed. "Proof!"