This idea just came to me, and I had to post it. I am a bit weary about it, so reviews would be nice.

Ian Chesterton sighed and looked back down to the book he was reading. It was a science fiction book and was quite good, but was a bit unconvincing The Doctor was busy fiddling with some piece of TARDIS equipment, and had been for a while now.

"Doctor?" Ian said, curiosity getting the better of him.

"Hmm? What is it, Chatterton?" the old man asked.

The science teacher rolled his eyes at the familiar name mistake. "I was wondering, what is that equipment you're fiddling with?"

"Ah. This, my boy is the Time Space Visualiser. It allows us to view any event in history. I'm just making some adjustments to it." The Doctor motioned to the book in Ian's hands. "How are you finding the book?" he asked.

"It's good. Far-fetched, but good." Ian answered. The Doctor smiled.

"Well, I'm glad to hear that." He turned back to the equipment and after a few minutes gave a nod of approval. "There! That should do it," the Doctor said, a hint of triumph in his voice. He put his hands on the console and lifted himself up, a light groan escaping his lips as he did so.

Ian frowned, worried for the man. He walked over to the Doctor and put lightly put his hand on his shoulder. "Are you okay Doctor?" he asked, concern clear in his voice.

"Yes, yes I'm alright," the Doctor answered with a gentle smile. He hesitated for a moment, wondering if he should tell the young man.

"What is it Doctor?" Ian asked, seeing the contemplative expression on the Doctor's face.

"I'm an old man, Ian. My body's wearing a bit thin. Soon might be time for a renewal..." he answered softly. His mood suddenly changed, and he looked up at Ian with a smile. "No need to worry about that now. Live life in the present!" he smiled and turned back to the console, leaving Ian confused and worried.

They'd been back home for 6 months now. A chance to return home had arisen, and they'd taken it. Ian and Barbara where now husband and wife; their adventures with the Doctor had made them realise their feelings for each other. Ian had told Barbara about what had happened in the TARDIS console room that day, and even she agreed that it was worrying.

"What could he have meant with that?" she asked.

"I don't know." He simply replied. Every day they would wonder what he'd meant. They both hoped that they would see him again, to find out what he'd meant. But they both knew that it was very unlikely that they would ever see him.

A year after they'd left, one sunny day in March, they went for a walk in a nearby forest that they visited quite frequently. Not many people came down here so they were shocked to run into a strange man. He had longish, black rumpled hair and blue eyes. The way he dressed reminded Ian and Barbara of the Doctor (although not as smart or refined): clownishly large checked trousers, a bow tie, a plain white shirt, a pair of black shoes and a black frock coat.

"Oh, so sorry!" he hastily said.

"No, no it's alright!" Barbara replied. "It's a bit surprising, as hardly anyone comes down here."

"Ah! Makes it the perfect place to relax, have a stroll, clear your mind." He listed off, but then smiled cheerfully. "How are you two?" he asked happily.

They looked at each other, slightly confused by how friendly the man was being. Talking to them like they were old friends. "Were fine." Ian answered. "And you?" he asked.

"A bit worried, I'm a traveller you see," he said with a slight sigh. He opened his mouth to carry on but he suddenly turned around. In the distance Barbara and Ian could hear two voices calling out, but they couldn't hear exactly what was being called out. However, as the voices got closer their eyes widened with shock and they turned to each other.

"Doctor! Doctor where are you! Doctor!" the two voices called out.

The man sighed and turned to them. "Sorry, I must go." He turned around, and headed in the direction of the voices. Barbara gasped and turned back to Ian.

"The Doctor!" she mouthed to Ian, and he nodded.

"Wait!" Ian called after the man. The man jumped in surprise and swiftly turned round.

"What?" he asked, frowning slightly.

"Doctor?" Ian and Barbara asked and the man smiled.

"Yes Ian and Barbara," He simply said

"But how?" Barbara asked. "How can it be you?"

The Doctor sighed again. "Remember what I said, Ian? In the console room, the same adventure both of you left."

"You said that you were wearing a bit thin, and something about a renewal." Ian recalled.

"It wasn't me that was wearing a bit thin. It was my body," he corrected. "Renewal is where the body is healed after fatal injury or old age. An ability of my people. The side affect is that the physical appearance and personality changes," the Doctor explained. He turned around and put a hand up. Ian and Barbara looked up and saw a man and a woman standing on a hill. The Doctor looked back at Ian and Barbara. "I'm terribly sorry! Jamie and Zoe are waiting. I must go," he said.

"Goodbye Doctor," they both said.

"Goodbye and congratulations to you two. I received your letter Ian," he smiled and Ian smiled back. The couple thanked their old friend. The Doctor turned and jogged over to where his two companions were standing. Briefly talking to them, the three of them turned to the couple and waved goodbye. Ian and Barbara smiled and waved back. Then they turned and disappeared over the hills. After a few minutes they heard the whirring of the TARDIS engines, and both smiled at each other.

They had finally found out the answer.