"Would you take that hat off?"

"No."

"It's my hat."

"You said yourself that you haven't worn it in two hundred years. I think that counts as abandonment, don't you?"

"Not if I left it in my own home."

"Ah, but it's not your home. You stole it."

"Borrowed."

"Seven hundred years ago! When exactly are you planning on returning it?"

"Maybe I would if the museum were still there."

"Well, I'm borrowing your hat," Harry said with finality, crossing his arms. "It was blooming bad enough out here last night, and now you've got me walking around in this stifling heat in the sunlight. I'll die, Doctor. I will just drop dead from heat exhaustion and it'll be your fault."

"Then we'll get you your own hat."

"No need," Harry answered with a grin. "I have one."

They had been arguing with each other nonstop since they left the TARDIS, but at least they were in good spirits. Wilf used to worry about how much they fought but they strangely seemed to experience some kind of glee when they argued.

Jack had muttered in his ear and told him they were flirting, but he wasn't really sure. He had suspected that Harry might have some romantic feelings for the Doctor, but he highly doubted that the Doctor returned them. It wasn't so long ago that the two could barely speak to each other, after all.

But maybe Jack was right. He didn't know much about Time Lord culture so it was difficult to know where their people drew the line between platonic and flirtatious behaviour, but if they were human he would think it was the latter.

They had been sort of drifting together since last night. If the Doctor stopped to look at something then Harry would stop as well, even if he seemed to have no interest in what the Doctor was looking at, and vice versa. He'd seen them holding hands again as well—but did it imply the same thing on Gallifrey as it did on Earth?

"Perhaps we should take a little rest from the sun, Doctor," he spoke up. "It is pretty toasty today."

He actually didn't think it was all that hot, but someone who looked old asking for a rest usually got better sympathy than someone who looked young. He was worried about taking Harry out enough as it was, not wanting to overbear him with activity and cause an attack, and now that they were out in the sun he worried more. He could see that Harry was tired, even if the Doctor didn't see it, and he knew that the poor lad would start feeling ill if they didn't give him a rest soon.

"Yeah, let's give the kids a break," Jack agreed, squinting up at the relentless sun. "I know there's a clearing over that way where they have street performers a lot of the time. We could grab a drink, find a spot in the shade, and see if we can catch a show."

Harry made an exaggerated gasp of excitement. "Maybe we'll see your acrobats!"

Jack mimicked the gasp perfectly and returned the look of mock excitement. "Maybe they can teach you some of their tricks!"

It didn't take long to find the place Jack was talking about, and he was right about the street performers. They were still setting up a lot of complicated equipment but he decided that was a good thing because it meant they would wind up waiting for the show to begin. The area had several long benches set around the perimeter of the clearing specifically for the viewing of such shows, and Harry made a bee line for the closest one in the shade.

"You guys get comfortable," Jack offered kindly. "I'll go get some drinks."

He stole a glance at Harry and saw that his face was completely different when he didn't think anyone was looking at him. He had learned by now that Harry wasn't really taken seriously when he complained because he usually did it in a teasing or joking manner, but that didn't mean his complaints weren't real. The poor boy looked quite unwell.

"Have a lie down, Harry," he suggested, noting the way Harry immediately brought a smile to his face again once he was aware of someone watching him. "Kick your shoes off too. It'll help you cool down."

For once, Harry obeyed without so much as a smart comment. The bench was narrow and made of hard stone, but he looked much happier being able to lie down. That seemed to help the Doctor realize that Harry was not complaining for the sake of being annoying for he quickly took off his suit jacket, rolled it up, and offered it as pillow.

"Thank you, Doctor," Harry muttered, stuffing the jacket under his head while being very careful to keep hold of the old hat in his free hand. "But I'm still not giving back the hat."

"Keep the stupid hat. Excuse me, Wilf," the Doctor stepped past him so that he could sit by Harry's feet. Wilf decided to sit by Harry's head where he could keep an eye on him while the Doctor lifted Harry's feet onto his lap and started undoing the laces on his shoes.

"Don't take my shoes off," Harry groaned but made no attempt to pull his feet away and the Doctor pulled them off anyway. He simply sat there, one hand resting on Harry's leg and the other holding one of his feet, and watched silently as the performers set up.

Jack returned a minute later with drinks for everyone. "I asked them to flavour yours with a little arsenic and just a pinch of cyanide," he said cheerfully as he pushed a cup into Harry's hand. "Should give it a bit of a kick."

"Mm, my favourite," Harry didn't even sit up to drink, just popped the straw in his mouth and drank it lying down.

"What did you put in mine?" the Doctor asked when Jack gave him his drink.

"Don't worry, you won't mind once you drink it."

It was another fifteen minutes of watching the performers set up and listening to Jack telling them stories about his days as a travelling performer before the show started. It turned out to be a magic show, starting with a few simple disappearance tricks and gaining momentum until the performers made it temporarily rain over one single person and made one of their own members appear to change species.

So many of the things he saw seemed absolutely impossible though he didn't say much because he was sure that the others in the group were clever enough to know how the tricks were done. Whenever he peeked down at Harry's face he could see a content smile and he was glad to see that the Doctor was smiling too, though he couldn't imagine having Harry's feet right beneath his nose was pleasant on a hot day.

They spent the next couple of hours drifting from one show to another, letting the hottest part of the day pass with as little physical activity as they could manage. Once it began to cool a little Harry seemed to get his energy back and they returned to all the exciting activities of the park, dragging Jack around to all the things he had missed the night before. But when Wilf mentioned that they had all danced together, Harry threatened to break Jack's fingers before the poor man was even able to say anything. The Doctor quickly decided that they'd all done enough dancing the night before.

The day slipped by happily. Even with Harry and Jack bickering every ten minutes, everyone seemed to be in a good mood. He only wished that Donna had been feeling better and joined them—with her along it could have been named the perfect day.

The sun went down and the world was alive with lights again. He thought that Harry would be comfortable once it got dark, but he began to complain about the heat again. The sun may have disappeared but the countless number of lights beaming down on them every moment did produce an awful lot of heat, and Wilf had to admit himself that it was quite warm.

However, it wasn't until he got physically ill that anyone really took the complaints seriously. They had gone on one of those mad rides that spin and fly and do all sorts of impossible things. It was normal to feel a bit off once it was over, considering that everything in your stomach had been flipped upside down several times, but Harry finally couldn't take anymore and looked perfectly white in the face.

"What's the matter?" Jack had teased while Harry stayed unnaturally quiet. "Can't take it rough?"

"Jack, don't," the Doctor said quietly and touched Harry on the shoulder. "Are you alright?"

Wilf just shook his head and took the poor lad by his arm, leading him over to the nearest garbage can. As they neared it, Harry suddenly quickened his steps and reached the bin just in time. Jack hurried off to get some water while he stood with Harry and patted his back. The Doctor stayed quiet, though he looked terribly concerned, and fidgeted the whole time.

"We should take him home," Wilf insisted. "He's done too much since yesterday without enough rest. We should have both known that when he slept in this morning—he obviously needed it."

The Doctor nodded in agreement quickly. "You're right."

After a couple of minutes Harry seemed to think that he would be alright and dared to venture away from the garbage can. Jack pushed the cup of water into his hands and they all sat and waited while he sipped at it and caught his breath.

The walk back was stressful because they didn't want to rush Harry and overexert him again, but they also wanted to get him back as soon as possible. Wilf noticed that Harry's fingers were beginning to twitch and that his eyes were gaining a confused and faraway look. He thought he would keep that quiet, not wanting to worry the Doctor any more than he already was, but it wasn't long before Harry's behaviour slipped.

Harry stopped quite suddenly and looked around him, staring into the crowd with knitted eyebrows. "Where's Kahlia?"

He felt immediate sadness. He looked into those worried brown eyes and remembered the day that he and Sylvia couldn't find Donna and how awful that had felt. This would be so much worse.

"She's not here," the Doctor said quietly, taking Harry's hand and trying to keep him moving. "Come along."

"No, no," Harry insisted, pulling his hand free and scanning the crowd again. "She was right here. Where's she gone?"

"Who's Kahlia?" Jack piped up.

The Doctor simply waved his hand in annoyance to shut him up and tried to get Harry's attention again. "We left her in the TARDIS, remember? We're going back right now to go see her."

"The TARDIS?"

"Yes. It's this way."

But Harry simply looked at them all with even deeper confusion. "She's never been in the TARDIS."

"Not until today," the Doctor persisted.

"What is wrong with him?" Jack was asking Wilf now, muttering under his breath while the Doctor kept talking. "And who's Kahlia?"

"This is just what happens sometimes when he's not well," Wilf explained. "His memories get all mixed up and he gets confused."

"She was right here!" Harry suddenly shouted. "She must have wandered off. We need to look for her."

"Harry, listen to me," Wilf stepped forward and grabbed Harry's shoulder, making sure to look him in the eye. "Listen to me, my boy. Remember where we are. Remember when we are. It's just you, me, the Doctor, and Jack and we're walking back to the TARDIS. We'll get you a lovely dinner and you can have a nice long sleep and everything will make sense in the morning."

He was happy to see that Harry seemed to calm down a bit when he spoke to him, though he was still distressed. "But if she's not with us then where is she?"

"She's gone, lad," he answered in as kind a voice as he could muster, squeezing Harry's shoulders in comfort. "Let's get back to the ship and we'll talk about it, alright?"

"She's gone . . ." Harry swallowed hard and looked carefully at each person in the group in turn, analyzing them carefully. "She never saw the TARDIS. She never met any of you."

"That's right," the Doctor answered. "Just take a second to think about it. You can figure it out."

Harry nodded his head quickly. "It's just . . . she was right here."

"But that was a long time ago."

"A long time ago," Harry repeated, the look of confusion in his eyes slowly being replaced with sadness. "And . . . she's dead now, isn't she?"

"Yes. I'm sorry."

"Oh," Harry glanced around at the crowds of children surrounding him and nodded his head again. "Does her mother know?"

"Yeah," the Doctor slipped his arm around Harry's shoulders and began to lead him in the direction of the TARDIS again. "It's been a long time. She knows."

"Okay," Harry walked along, taking in deep breaths and looking around him carefully. "Which parts are real?"

"We're real," Wilf answered him quickly, leaning forward as he spoke to make sure that Harry could see him. "There's me, the Doctor, and Jack. The people around us and all the lights are real. It's safe here, don't worry."

Several minutes passed in silence. Harry walked along peacefully, looking about him with a frown on his face, trying to sort reality from memory.

He knew this was going to happen. He had said so many times before they even left the ship and several times afterwards. Harry had been doing very well lately—someone who didn't know him would never guess that anything was wrong with him—but that didn't mean he was better. Harry was still sick and everyone knew it, but they had still taken his healthy behaviour for granted. The trip last night had been pushing it as it was, but taking Harry out again the next day had been stupid.

They were almost at the ship when Harry suddenly pulled away from the Doctor, eyes wide as he turned to the crowds. "Kahlia!"

"God damn it," Jack muttered, grabbing a hold of Harry's arms to stop him from running off. "Who the hell is Kahlia?"

"My daughter," Harry spat back, trying to wrench his arms free. "She can't have gone far. Kahlia!"

He stepped forward, catching Harry's eyes again and speaking slowly. "Harry, remember what's happening. You're sick and your memories get mixed up sometimes. Kahlia died a long time ago."

"She's not dead!" Harry insisted. "I can hear her. I can still hear her! We have to go back. Doctor!"

They were drawing the eyes of the crowd now, making the whole situation a lot more uncomfortable than it already was. Jack simply ignored the glares of strangers and kept his iron grip on Harry's arm, keeping him beside him.

"We have to get you back to the TARDIS," the Doctor said calmly. "I'm sorry, Master, but she's dead. We need to take care of you right now."

"She's still in there," Harry's voice dropped to a whisper, staring intently into the Doctor's eyes. "Why won't you just go back? Doctor, please, we can get her out. She might still be able to regenerate."

If Wilf hadn't been looking directly at the Doctor at the time, he would have missed it. There was a split second in which every ounce of strength in the Doctor seemed to falter. His face changed to one of great sadness for just the briefest of moments before he forced himself back together.

"Jack, drag him, pick him up, I don't care what you have to do," the Doctor ordered, glancing at the many watchful eyes in the crowd. "We need to get him to the ship before this gets any worse and he becomes dangerous."

"Dangerous?" Wilf sputtered as Jack immediately began to haul Harry away, ordering the crowd to clear the way and claiming to be security. "Doctor, he's just worried about his little—"

"He's not talking about Kahlia anymore," the Doctor interrupted. "Trust me, if he delves any deeper into this memory, it could be very dangerous. I can't have him getting violent in a crowd like this. We need to get him on the ship where I can deal with him myself."

"But what on Earth happened?" he asked. "What memory is it?"

They reached the ship and the Doctor hurried forward to unlock the door. Harry kicked and fought as Jack dragged him through, growled threats escaping his mouth in a different language.

"It's a bad memory—the day we became enemies," the Doctor said with a pained expression as he locked the door shut behind them. "He's reliving the day that he first tried to kill me."

Wilf couldn't bear to think of what was going through poor Harry's head at this moment. "What happened?"

"Doctor!" Jack shouted, struggling to keep Harry under control. "Can we get a sedative or something? He's a bit stronger than he looks!"

The Doctor looked him in the eye, heavy with the weight of his memories. "I killed him first."