"How would you like to see a magical city called New York? So after breakfast, pack a suitcase. It's time for you to see the world."

Belle smiled sleepily. She could have told Rumple what they both already knew: that she had seen more of the world than just New York, but he hadn't been there with her to see it. But no. No point in spoiling the moment. She was going on a trip with her husband, and that was worth being happy about, even if he couldn't take her to far-off galaxies or distant futures.

But before she went, she was going to see the Doctor again. So when Rumple left her alone in the shop, she pulled out her phone. Only moments later, a familiar whirring noise filled the air, and the Doctor's blue police box materialized in the back room.

"Welcome to Euphoria, voted the happiest town in the galaxy for three straight decades."

Belle and Martha exchanged a grin.

"Should make for a change from all the running and screaming," Martha commented.

"Oh, I don't know about that," said the Doctor. "I don't know about that at all."

"What do you mean?" asked Belle.

"Well … I'll just let you see for yourselves, I suppose."

He opened the TARDIS door, and the first thing Belle noticed was how blindingly bright the world was. Not bright like the walls of a hospital, white and cold. No, this world was warm and full of color. Houses were painted bright shades of yellow, flowers bloomed along the sides of the road, and even the sky looked bluer than it did on earth. Every garden had a white picket fence. Belle smiled.

"Beautiful," said the Doctor. "Beautiful, and so, so wrong."

"Why wrong?" Martha asked, looking around in wonder.

"Because this system should be in ruins," said the Doctor. "It was hit hard by the Time War, and this planet is the only one left where there's still life. There's no way they should be prospering like this."

"You'd rather they were suffering?" Belle asked.

"No, of course not. But …" his voice trailed off. At the nearest house, a man had come out the front door, whistling.

"Hello, there!" he cried, waving to the three of them. "I don't mean to be rude, but I don't think I've seen you around before."

"Oh, we're just passing through," said the Doctor, pulling out his psychic paper and handing it to the man. "That should explain it."

Immediately, the man's posture changed. His back straightened, and his smile grew serious.

"Thank you for your service, Captain. If there's anything I can do to help you …"

"Actually, there is," said the Doctor. "You see, I'm not quite sure where I'm going, so if you could just point me in the right direction …"

"Of course. Guard headquarters are just two blocks down to the right."

The Doctor exchanged a glance with Belle and Martha, and they set off in the direction the stranger had told them.

It was the only building on the street not painted yellow. Instead, it was a pale brownish-gray that seemed designed to fade into the background. The Doctor showed his psychic paper at the door, and they were ushered inside, past an empty lobby and into an office with a heavy-looking metal door. A large, fat man in a suit sat behind the desk.

"I'm General Jamison," he said. "Welcome to Euphoria. I have to say, when I asked for more guards, I didn't think I'd get any," he said, looking them over with a critical eye.

"Well, everybody's quite interested in what you're doing here," said the Doctor. "And they quite want to make sure you succeed."

"I assume you and your assistants have already been briefed on your duties?"

"Actually, just to clarify, could you go over them again?"

The General rolled his eyes. "It's quite simple. We keep Euphoria happy."

"And how exactly do we do that?" the Doctor asked.

"By facing reality for them. You'll understand soon enough. I'll send you out with an experienced member of the guard."

He pulled out something that looked a bit like a phone and pushed a couple of buttons.

"Sargent Collins? I have a couple of new recruits for you."

Sargent Collins turned out to be a young man who looked at them as if he was looking right through them.

"Right," he said. "Come with me. I'll show you what we're meant to be doing."

They followed the young sargent past blocks and blocks of yellow houses.

"Does everyone here paint their houses like that?" Belle asked.

"Oh, yes," said the sargent. "Yellow is the color of happiness, and given our situation, happiness is only right. Anything less would be ungrateful."

"Ungrateful?"

"Euphoria is the happiest city in the galaxy, and we've worked hard to make it that way. Here we are. The Border."

Belle raised an eyebrow. She opened her mouth to ask why, if Euphoria was such a perfect town, they needed such a large fence, but the Doctor beat her to it.

"Is it really so hard to keep them in?"

"In?" the young Sargent looked confused. "Captain Smith, the wall isn't about keeping anyone in. It's about keeping danger out."

"Out?"

He laughed. "They really didn't tell you anything, did they?"

As Belle and the Doctor exchanged a wary glance, the sounds of shouts and scuffles broke through the peaceful silence. Around the corner came two guards, dressed in the same uniform as Sargent Collins, dragging a frantic, sobbing young woman.

"I'm sorry! Please, I'm sorry!" she cried. "I won't tell anyone, please don't send me away, please, I'm begging you!"

But they dragged him past Belle and the others, up to the fence, where one of them slid some kind of card. A single metal plate slid out of place, revealing just a glimpse of darkness before the man was thrust out and the wall slid closed again. The only evidence that anything had happened was the faint pounding from the other side of the fence. A couple of children playing in a yard nearby just continued their game, as if nothing was wrong.

Because it wasn't, Belle realized. At least, not to them.

"What was that?"

"Someone who doesn't belong here," said Sargent Collins calmly. "All those who break the rules of Euphoria are banished. That's why there's such a low crime rate. No one wants to die."

"We'll get to the bottom of this, won't we, Doctor?" Martha said, after they been left at the wall with orders to make sure no one got through.

"Sure we will," he assured her. "There's something very wrong here."

"Isn't it obvious?" asked Belle. "Obviously, there's something bad out there."

"Oh, yes," said the Doctor. "But there's something wrong in here, too."

Walking up to the front of one of the yellow houses, the Doctor knocked on the door. Moments later, a woman answered, and he showed her the psychic paper.

"How can I help you, Captain?"

"I want you to tell me what's wrong with this town," he said.

"Wrong?" she asked. "There's nothing wrong. Everything is wonderful in Euphoria."

"But there's something not right," he insisted. "You know it. I know it."

She smiled blindly. "Of course not. Everything is fine."

"What's outside the wall?" he asked.

"Oh, you don't want to talk about that," said the woman cheerfully. "There's no need to worry about it."

"No need to worry about it?" Belle asked. "Aren't you scared of whatever's out there?"

The woman shook her head, a contented smile on her face. "Of course not. You'll protect us. And the walls are strong."

"Don't be silly," said Martha. "You can't possibly be so happy about living trapped in this little town with danger right outside."

"Everyone is happy in Euphoria," said the woman. "It would be wrong not to be."

On their way back into town, they were stopped in the street by Sargent Collins, who whispered something in the Doctor's ear too quietly for Belle or Martha to hear.

"What was that about?" Martha asked.

"Oh, nothing," said the Doctor. "Just a friendly reminder to keep my mouth shut, which I have no intention of doing."

"Aren't we going to get into trouble?" asked Belle.

"Well, I should hope so," said the Doctor. "Best way to find out what's really going on someplace is to get into trouble."

Belle wasn't quite sure if she liked that idea, but she wasn't about to say it. Anyway, she trusted the Doctor.

When they arrived back at the only dull gray building in town, armed guards were waiting for them.

"Well, I guess that answers the question about getting into trouble," said Belle.

The Doctor didn't protest as the guards led them back to the border, and even had the nerve to try to make small talk as they went. You would think he wasn't nervous at all, and maybe he wasn't. But Belle's stomach churned as they approached. The metal plates of the fence slid open, and they were all shoved out into …

… nothing.

Just vast, endless rocky wasteland, devoid of plants or trees or any sign of life. The worn-down remains of ruined buildings stood in the distance, some of them broken, as if a tornado had come through. Even the sky up above was no longer blue, but a cheerless gray. The air itself seemed heavy and thick, and Belle coughed a bit as she inhaled. Behind them, the gate slammed shut again.

"Devastation," said the Doctor. "I thought it must be …"

"What happened?" asked Belle.

"I told you," he replied. "There was a war. A horrible war that devastated entire star systems, this one included. And the world it left behind is dead. Hardly fit for humans to live in."

"How do they do it, then?" Belle asked. "What's the deal with Euphoria?"

"Oh, a good strong wall, an artificial sky, and oxygen filters," said the Doctor. "Aside from that, you'd be surprised what a few buckets of brightly-colored paint can do."

"But it's not real," said Belle.

"Course not," said the Doctor. "But I don't begrudge them trying to make the best of things."

"Then what are we doing here?" Martha asked. "I thought that was the point, that their happiness is fake."

"It is," said the Doctor.

"But …"

"Humans can do great things," he said. "And sometimes those great things come from suffering and hardship. A town that rises out of destruction and becomes a haven of peace and happiness … that's the kind of story I could get behind. But a town that enforces happiness at the threat of death and pretends the elephant outside the gates isn't there …"

Belle nodded, understanding for the first time what he meant.

"This wall isn't to keep a threat out, is it?" she asked. "It's not to protect them from danger. It's to keep them from having to face reality."

"Exactly," said the Doctor. "And tonight, it's coming down."

"Well, you won't be the first to try," said a woman's voice. Belle turned around and saw the same woman who had been thrown out of town earlier that day. Something about her face looked familiar. "No one gets back through that gate. I'm sorry, but … you're doomed."

"That's not going to work," the stranger said. Not that the Doctor was listening. He was too busy running his sonic screwdriver around the seams in the metal wall. "You can't just unlock it. Anyway, it's not as if they'd let you stay, even if you got back in somehow."

"He won't listen," Martha told her. "He's stubborn that way. I'm Martha Jones, by the way. You?"

The woman barked out a laugh.

"What?"

"We're all going to die out here, and you want to introduce yourself? Make small talk?"

"We're not going to die," said Belle. "The Doctor won't let that happen. I'm Belle French."

The woman was quiet for a moment. Then … "Stella."

Oh. Belle knew her face betrayed what she was thinking, and the Doctor froze, slipping his sonic screwdriver back in his pocket and turning around slowly. He looked closely at her.

"I thought I'd seen your face before," he said. "You were older then, but you've got the same eyes … the same chin … nice to meet you again, Stella!" he took her hand and shook it enthusiastically. "You can call me John Smith, and I can assure you we're not going to die here, because you've got a future somewhere far away from this planet."

She looked away, staring at the ground. "Don't say that. False happiness is cruel enough, but false hope …"

"It's not false hope, I assure you," said the Doctor. "We're getting inside that city."

"There! Done!" he declared.

"Um … Doctor?" Belle said quietly, staring at solid metal. "What's done? It's still sealed off, isn't it?"

"Exactly," said the Doctor. "We can't just force our way through. We've got to get them to let us in."

"They'll never do that," said Stella.

"They will," he said. "See, I've hijacked the video feed of their fake sky. You see that security camera up there? Everyone's seeing it projected across the sky."

"We can't do that!" Stella cried out, suddenly frantic. "No one in Euphoria likes to think about what's out here! Being forced to see it would break their hearts!"

"They threw you out here to die," he told her. "Do you really care about their feelings?"

Stella went quiet. Belle turned to the camera and spoke:

"I know this is confusing and scary for you. But you can't hide from the truth forever. It's one thing to find happiness in the face of suffering and another thing to ignore reality."

"You have to face the truth," said Martha. "The world you live in isn't perfect, and maybe you've gone too far trying to make it perfect."

"You threw me out just for finding out the truth!" Stella spat. "Just for crying when I found out the truth."

"Truth?" the Doctor's eyes widened. "What truth?"

"It doesn't matter," said Stella.

The Doctor looked at her for a long time, and Belle was sure he was going to insist that it very much did matter. But then he turned back to the camera.

"Your white picket fences and yellow paint are an illusion," he said. "And if they were a harmless illusion, I might not care. But they're not. You're hurting other people, you're hurting yourselves, and someone has to tell you, because you're so brainwashed you can hardly see it."

"Please let us in," said Martha. "Open the gates and face the truth before you have more blood on your hands."

Nothing happened. The gates didn't open, and whatever was happening on the other side, there was no way of knowing.

"It's no use," said Stella. "They don't give a damn."

Miserably, Belle sat down on the ground. Tears ran down her face, and she wiped them away, whimpering slightly.

"I'm supposed to be going on my honeymoon," she sobbed. "Rumple was going to take me to New York."

"You'll get to see it," the Doctor said, sitting down beside her and wrapping his arm around her. "Hey, listen. I promise. Have I ever let you down?"

She shook her head. No. He never had.

Hours passed. The sky went dark, and they curled up on the ground to go to sleep, while the Doctor sat up and kept watch. Stella suggested they head out for the half-destroyed city on the horizon, but the Doctor shook his head.

"We're not leaving," he said. "It won't do any good, anyway. Nothing can survive for long without Euphoria's oxygen filters."

"No one will live long anyway," said Stella. "That's the truth I found out. The oxygen filters – they're failing."

The Doctor stiffened and looked at her. "Are you sure?"

"Yes. They've been trying to fix them for months. But sooner or later, everything wears out, and they probably only have a few weeks left. No one knows. That's why they threw me out. They were scared I'd tell."

"And now you have," said the Doctor, standing up. He walked up to the camera and stared straight into it.

"I can get you out of here. I have a spaceship. I can take you someplace safe, probably not someplace as cheerful as Euphoria, but you'll have a chance, a future. Or you can let us die out here and let yourselves die in there. It's your choice."

A few moments later, they heard shouts coming from the inside of the city and fists pounding on the wall. Time passed - maybe minutes, maybe hours, it was hard to tell – and the metal began to fold under the force of dozens of people trying to force their way through. Then, it fell, and they ducked out of the way as it crumbled as easily as if it were made of the wooden blocks children play with. What looked like half the town stood there, some of them with battered chairs and gardening tools, others with bloody fists.

"Good choice," said the Doctor. "Very good choice."

"It won't be easy," the Doctor warned them as they piled out of the TARDIS. "Your lives won't be as perfect as they were in Euphoria."

"But we'll survive?" asked a man in the crowd.

"I hope so," he said. "The planet's inhabited – and habitable – and they're generally good about taking in newcomers. You should be all right."

As they left, Stella hung back. She looked at the Doctor as if understanding something for the first time.

"I'll see you again, won't I?" she asked.

"Yes," he said. "Years from now, when you least expect it, and I won't look the same. But you'll recognize the blue box."

"Goodbye, then," she said. "For now."

"Where to now, Doctor?" asked Martha.

"Cardiff. The TARDIS looks like she needs to be recharged. Want to come with us, Belle?"

But Belle shook her head. "I have a honeymoon to get ready for."

Belle heaved the suitcase shut. Or, at least, she tried to; stuffed as full as it was, it didn't want to close. As she wrestled with it, a young boy walked into the shop.

"Hey, Grandma," he said. (She would really have to talk to him about calling a woman in her early thirties "Grandma", whether she technically was or not). "Are you taking a trip?"

"Rumple's taking me to New York for our honeymoon."

When he told her about the spell on the town line, she just shrugged. There were always ways of getting back in, and Rumple was just as clever as the Doctor about things like that.

"Okay, so … I need another suitcase," she said. "Help me look?"

But when he tried to take one from a high-up shelf and sent a pile of things tumbling down, a certain gauntlet caught her eye. She paused, staring at it.

And when she picked it up and saw where it led her, all her illusions of happiness came crashing down on her.