Stepping out of the TARIS, sporting a rather fetching sombrero and sunglasses, the Doctor threw his arms in the air triumphantly.

"Mexi… co?" he cried, his voice faltering as he looked around him. Amy and Rory stepped out of the TARDIS behind him.

"This doesn't look like Mexico." She stated, flicking his hat in irritation. Scowling, the Doctor tightly gripped onto the edges of his newest fashion anomaly and backed away from her.

"That's probably because it's not." Rory said in exasperation, "Doctor, where are we this time?" Pulling off his sunglasses and shoving them unceremoniously onto the top of his hat, the Doctor looked around.

They were stood on what looked like a suburban street corner. The houses were generously spaced and clearly belonged to the more affluent families, their white picket fences and clean concrete drives reflecting the sunlight as money reflects material wealth. Across the street and to the right there was a children's play park, surrounded by flawless green grass. Parents sat on benches, making polite conversation as their children played contently. Young couples lay on the earth, basking in the rays of crystal clear light. The sky above them was such a vivid blue that it gave the impression that the whole world was in a bubble.

The Doctor breathed in deeply. He could smell… pears. Definitely pears. He convulsed slightly at the thought of such a fruit. But there was something else. The air was so pure, so… perfect. But at the back of his mind the Doctor could have sworn he smelt something that was out of place.

"Something's wrong…" he muttered to himself. Closing his eyes and wrinkling his nose, he tried to focus on it.

Soon he felt a gentle tap on the shoulder.

"Aren't you going to tell us where we are?" Amy whispered loudly in his ear.

"Domicilia, near the end of the fiftieth century." The Doctor replied, opening his eyes and whirling around to face his friends. He grinned childishly, hiding his doubts, "This is the very first human colony to have survived off Earth, hence the name Domicilia."

"Domicilia?" Rory asked.

"Latin for 'new home'." The Doctor said. He was determined to find out what his tingling timey-wimey, pear-hating senses were picking up. Never ignore a coincidence. Or was it, never ignore your instincts? Either way, he was going to stay until he found out what that smell was. Focusing on the confused pair before him, the Doctor continued, "Let's explore, shall we?"

"While you're wearing that hat?" Amy asked incredulously.

"Yes, while I'm wearing this hat." The Doctor answered protectively, "Sombreros are cool." As Amy rolled her eyes, he turned around and began walking off down the street, towards the park. Without checking to see if his friends were following him, the Doctor began sniffing irregularly, attempting to stimulate his thoughts.

He had smelt that smell before, a very long time ago though. But where? And when? Marching past the park, his head down and his hat tilted, the Doctor continued on his quest. By now the park was behind him and he was fast approaching the middle and lower class streets. The houses were less crystalline, but were still fairly new in appearance. They had slightly less space on either side and they looked considerably smaller than the houses further back.

Muttering to himself in frustration, he ignored the calls of Amy and Rory, focusing on his goal. Where had he smelt it? Where? Usually he could tell apart time zones simply by smell. What was wrong with him? And then, like a bitch slap from an iceberg, it hit him.

"Gallifrey…" he whispered, halting immediately in shock. He barely noticed Amy's lively chatter or Rory's replies constantly being interrupted by his wife. The Doctor could think of nothing more than what he had just realised: there was a Time Lord on the planet. This planet. Right now. Or at least someone of Gallifreyan descent.

Tears began to form in his eyes as an unusually large surge of emotion flooded over him. He was confused, ecstatic, and alarmed, all at once. But mainly alarmed. Surely if another of his kind had survived the Great Time War he would have felt it. He was certain, in his heart, he would have been able to tell. Time Lords had active telepathic sensors in their brains. They could tell if another of their kind was nearby, nearby, for Time Lords, meaning within the galaxy. It was a bit like telepathic Facebook; when someone was online, they would appear on the list. The more the Doctor contemplated the situation, the more his fear dominated every other emotion. But curiosity still bubbled away in the background. If another Time Lord still lived, it was his duty to find them.