"Just one trip, that's what I said. One trip in the Tardis and then home." Sat beside Martha by the console, I send him a pout. He can only hold eye contact for a little longer before giving in. "Although I suppose we could... stretch the definition. One trip in the past, one into the future. How do you fancy that?"

"No complaints from me," she excitedly replies.

I get up, joining him in his examination of the yearometer. We share a sideways glance and I smile in teasing thanks for his lenience. With faked annoyance, he sighs, "How about... a different planet?"

Her face lights up just at the idea. "Can we go to yours?"

In an instant, his amused expression fades, darkening into one of poorly masked sadness that I have gotten painfully used to by now. "Nah. There's plenty of other places."

"Come on, though! I mean, planet of the Time Lords? That's gotta be worth a look. What's it like?"

"It's beautiful, yeah."

"Is it, like, you know, outer space cities — all spires and stuff? Great big temples and cathedrals? With lots of planets in the sky?" she continues, oblivious. She doesn't see his pain.

But I do. I see far more than anyone could. He can try to hide his feelings and bottle it all up as much as he likes but I know him. I know how his jaw clenches, how he holds himself tensely, how the air around him seems to grow heavy with the weight of his grief. I know it and I feel it myself. My hand slips over the ridges and hills of the various controls, coming to rest on his. Slowly but surely, he turns it until our fingers mesh as they always do.

If I were vainer, I might notice the slackening of his shoulders and the parting of his lips and note them as some effect of my presence. Instead, I force myself to look away from him and gently ask, "Martha, can you get that lever over there?"

It isn't her fault. She doesn't know him well enough to read his tells. Nobody would ever imagine the kind of loss he has suffered; it is too great and too terrifying. Any frustration I would normally feel at these reminders for him fades quickly.

The silence is only broken by his far-off voice, "The sky's a burnt orange... with the Citadel enclosed in a mighty glass dome, shining under the twin suns." He turns his eyes to the ceiling but I'm sure he sees something far more like home than these metal walls and coral pillars. "Beyond that, the mountains go on forever; slopes of deep red grass, capped with snow."

He has never spoken of Gallifrey before. Never.

My attempts to divert the conversation falter from pure shock. All I can do is stare at him, waiting for our eyes to meet. In their chestnut tones, I can see the turn of my own home — great stone pines and amphitheatres, citrine skies and temple hearths. Everything beautiful and thriving and almost lost.

When I come back to the comparative coldness of the Tardis, I find that he is still watching me. He knows where my mind went, he pictured it just as clearly as I pictured his home. Sometimes I wonder if there is some sort of link between our minds. We empathise on a level that surely can't be normal.

"Can we go there?" Martha gasps, entranced. Her question snaps us out of our memories.

The barrier that had finally started to weaken builds back up and everything we saw vanishes in a blink. "Nah! Where's the fun for me? I don't want to go home!" Our hands part as if burned and he dodges around to the other side of the console, punching a series of random buttons until the pistons come to life. "This is much better. The year 5,000,000,053, planet New Earth. Second home for mankind. Fifty thousand lightyears from your old world, and we're slap bang in the middle of New New York. Although, technically speaking—"

"It's the fifteenth New York since the original," I interject, already seeing where this is going, "so it's—"

"New New New New New New New New New New New New New New New York. One of the most dazzling cities ever built."

 I hurry to catch up to them, barely having time to hear her surprised yelp as we step out into a deluge. "Oh, that's nice!" she complains, trying to zip up her jacket before her clothes can get more soaked. "Time Lord version of 'dazzling'!"

He only shrugs, amused by the sight of me struggling to pull his trench coat over my head. "Bit of rain never hurt anyone."

"Clearly you've never been caught in a Venusian acid storm," I mutter.

"Let's get undercover."

By the time we get into an alley, the rain has already eased off a little. We jog under the shelter of the looming flats, finding ourselves surrounded by dingy brick walls and rubbish. Hugging herself tightly, Martha looks around. "It looks like the same old Earth to me. On a Wednesday afternoon."

I chuckle, "Well, that's humans for you. Lost your sense of elegance."

"Hold on, hold on. Let's have a look," the Doctor says, leading the way over to an old information checkpoint. With a little encouragement from his sonic, the screen fizzles on. A woman appears, dressed smartly and wearing a fake smile that easily identifies her as a reporter. "And the driving should be clear and easy, with fifteen extra lanes open for the New New Jersey Expressway."

Her image disappears, replaced with a video of jagged spires beyond grassy cliffs and sea, swarmed with trails of flying cars. He breaks into a grin and points enthusiastically at it, looking at me. "That's more like it. That's the view we had last time, remember?"

The fond memory brings a smile and a world of pain. "I remember. Apple grass and cloud gazing." And Rose, I want to add. He hears it despite my silence and quickly returns his attention to the alley.

"This must be the lower levels, down at the base of the tower. Some sort of Undercity."

Martha does not seem so impressed. "You brought me to the slums."

"Much more interesting! It's all cocktails and glitter up there. This is the real city."

She rolls her eyes and scoffs, "You'd enjoy anything."

It's almost odd to see him with his hair all flattened by the rain, clinging to his forehead. "That's me!" he chirps. "Ah, the rain's stopping. Better and better!"

I follow him out from under the shelter, daring to lower the coat from over my head. Her footsteps rush after us. "When you say 'last time', was that you two and Rose?"

His nose twitches and he looks around again. With nothing to distract him from the question, he has to answer. "Um... yeah. Yeah, it was," he quietly says.

"You're taking me to the same planets that you took her?"

I hesitate, feeling her gaze dart over to me. Now that I consider it, maybe she has a point. It is odd to bring us back. We never visit the same place twice if we can help it.

The Doctor is far less self-aware. "What's wrong with that?"

At his apparent obliviousness, she straightens, shoves her hands in her pockets and walks on. "Nothing. Just, ever heard the word 'rebound'?"

Neither of us has a chance to apologise. A large hatch opens up to reveal what looks like a street food cart and a man sticks his head out. The space around him is off-white and mostly sanitised — as much as anything can be in this place. I can see no clear menu or condiments, only a few translucent bottles marked with the green, crescent logo for hospitals. "Oh, you should've said. How long have you been there? Happy! Do you want some Happy? Happy Happy."

Behind us, another opens. "Customers, customers. We've got customers."

"We're in business!" another cheers. "Mother, open up the Mellow!"

"Happy Happy, lovely Happy Happy."

"Anger! Buy some Anger."

"Mellow, makes you feel bendy and soft all day long."

"Don't go to them, they'll rip you off. Do you want some Happy?"

Sending him a suspicious glare, the Doctor mutters, "No, thanks."

Their shouts of various products continue in a jumble of noise. Martha can barely make herself heard. "Are they selling drugs?"

"I think they're selling moods."

"Same thing, isn't it?"

Finally, their attention is divided by a new potential customer. I follow their shouts to the thin, pasty girl stumbling towards us. She hugs a rugged, grey shawl around her head to escape from the chill winds. "And what can I get you, my love?" the Mellow vendor asks with a brief, triumphant glance at her competitors.

The girl forces the words out as if expelling their weight from her tongue, "I want to buy Forget."

"I've got Forget, my darling. What strength? How much do you want forgetting?"

"My mother and father, they went on the Motorway."

We slowly approach, cautious not to scare them off. The vendor fakes a pitying groan but I imagine it must be good for her business. "Oh, that's a swine! Try this, Forget Forty-Three. That's two credits."

Now the Doctor takes his opportunity before she can use the unseen product. He reaches out to stop her as she passes. "Sorry, but, hold on a minute, what happened to your parents?"

Her sullen face seems to grow more despairing by the second. "They drove off."

"Yeah, but they might drive back."

"Everyone goes to the Motorway in the end. I've lost them."

Whatever she is hinting at is lost on us. Surely, in a world of advanced technology and travel, driving to another place does not signify this kind of grief. "But they can't have gone far, you could find them." 

Her dull eyes well up with tears. She doesn't allow them to spill. Despite our warnings, she sticks the patch to the side of her neck. In an instant, the weight is lifted and she smiles. The light gradually returns to her eyes. "I'm sorry, what were you saying?"

"Your parents — your mother and father — they're on the Motorway."

"Are they?" she says with a vague, unfocused tone. "That's nice. I'm sorry, I won't keep you."

We watch as she vanishes into the steam of the Undercity, gone as if she was never here at all.  Martha bitterly remarks as I approach the Doctor, "So that's the human race five billion years in the future, off their heads on chemicals."

His back is still turned. I go to place a hand on his shoulder but the sound of a muffled cry catches my attention. Turning, we are both startled to see a man dragging her away. "I'm sorry. I'm really, really sorry. We just need three, that's all!"

His partner aims her gun at us. It doesn't scare me. I take a step towards her, prepared to disarm her, but am pulled back before I can. "What are you doing? Get off her!"

"I'm warning you, let her go!" Their continued apologies do nothing. "Whatever you want, I can help — the three of us can help you — but first, you've got to let her go!"

Another attempt to advance on them is stopped as the Doctor secures his hold on my arm. When I manage to shove him away, the fire exit has already shut behind them. He snatches his sonic screwdriver from his pocket and sets to work trying to unlock it.

The door slowly swings open. I lead the way down the corridor, relying on my inherited strength to sprint as fast as my legs will take me. Another door brings us out onto a fire escape.

A box-like car speeds off from the ground. "Martha!"

There has to be enough time for me to at least jump onto it. I set a foot on the railing but am dragged back again. Anger overboils before I know it and I push him away again. "What in Tartarus are you playing at? I could have stopped them! What, are you scared to get attached after Rose? Don't you get it? It doesn't matter. It can't. Martha has a life, and a family! If we don't bring her home after what you just did, it's your fault."

His stunned expression is enough to make me regret my words in an instant. It's too late to take them back. Instead, I head back down the corridor, searching for any evidence that the kidnappers may have left behind. There is nothing.

He follows behind, stone-faced, his hands deep in his pockets. The offended demeanour I expect to see is actually one of shame and frustration. He passes me, storming right up to the closed trucks and banging insistently on one of them. It opens up to reveal the beaming face of one of the mood vendors. "Thought you'd come back," she chirps. "Do you want some Happy Happy?"

"Those people, who were they? Where did they take her?"

Another hatch opens up behind us. "They've taken her to the Motorway."

Her enthusiasm fades a little and she sighs, "Looked like carjackers to me."

"I'd give up now, darling, you won't see her again."

"Used to be thriving, this place — you couldn't move. But they all go to the Motorway in the end."

I roll my eyes, glaring around at them. "You've got to have something more than that. Spill, because our friend has been kidnapped and I'm not past breaking a few bones if it brings her back."

For someone who usually opposes most sorts of violence, the Doctor does nothing to warn me against my threats. "He kept on saying three, 'We need three'. What did he mean, three?"

Sending a cold look my way, she answers, "It's the car-sharing policy, to save fuel. You get special access if you're carrying three adults."

"How do we get there?"

"Straight down the alley, keep going to the end, you cannae miss it." Without hesitation, we head into the steam clouds and plastic curtains that allow us further along, only pausing when she calls out again, "Tell you what, buy some Happy Happy, then you'll be smiling, my loves!"

Now they've done it.

Rounding on them, the Doctor snaps, "Word of advice: all of you cash up, close down and pack your bags."

She sours. "Why's that, then?"

"Because as soon as I've found her alive and well — and I will find her alive and well — then I'm coming back, and this street is closing. Tonight!"

—

Just as she said, we follow the alley down until we reach a locked door. The sonic whirrs against it until a quiet click signifies its unlocking.

The tunnel we find ourselves in is vast and carries on far out of sight. Lanes of cars hover, all honking and revving. Despite all of the pipes and extractor fans lining the walls, the air is thick with a yellowish haze.

My lungs seize the second it hits me. Coughing and retching, I hurriedly shield my face with the folds of the Doctor's trench coat still wrapped around me. I can already feel my head start to spin. Seeing me struggle, he stifles his own gags and reaches to steady me, nudging me back towards the door. We don't get a chance to turn back before the car closest to the platform opens up. A figure masked by a long scarf waves urgently to us. "Hey, you daft little street struts! What are you doing, standing there? Either get out or get in. Come on!"

Not needing to be asked twice, we stagger for the shelter and fall inside. Already I can see dark spots swimming across my vision. An oxygen mask is offered to the Doctor but he shakes his head, helping to put it on for me instead.

The second it is secured, I draw in a desperate gasp, my throat already raw from coughing. The clear air is a relief after those noxious fumes. Darkness takes over for just a moment as I recover, and I find myself stumbling again. Gentle arms catch me as I struggle to get my breath back.

Once I am certain I can breathe on my own, I ignore his mumbled protests and push the mask over his mouth and nose. He still keeps an arm around me just to be sure. A brief but silent disagreement over who should get the mask results in a decision to share, taking a few moments each before passing it over. Slowly, the fog in my head starts to clear.

"They're just standing there, breathing it in," our saviour exasperatedly explains to the woman sitting in the passenger seat of the vehicle. He removes his scarf and goggles to reveal the ginger stripes and whiskers that instantly identify him as Catkind — just like the nuns at the hospital we had visited so long ago. "There's this story, says back in the old days, on Junction Forty-Seven, this woman stood in the exhaust fumes for a solid twenty minutes. By the time they found her, her head had swollen to fifty feet."

The woman scoffs, "Oh, you're making it up."

"A fifty-foot head, just think of it! Imagine picking that nose."

"Stop it! That's disgusting."

Glancing back at us, he sends her a teasing nudge. "Did you never pick your nose?"

She goes to respond but stiffens, pointing out of the windshield at the barely visible rear lights ahead. "Bran, we're moving."

He rushes back to his seat and restarts the car with a mutter, "Right, I'm there. I'm on it." We stop not even half a minute later. "Twenty yards. We're having a good day. And who might you two be? Very well dressed for hitchhikers."

Taking the oxygen mask off, he presses it securely into my hands. I put it aside. Now that I can stand properly, I still find myself having to stoop due to the low ceiling. "Thanks. Sorry. This is Inara, I'm the Doctor."

"Medical man!" He lets out a sound halfway between a laugh and a purr. "My name's Thomas Kincaid Brannigan, and this is the bane of my life, the lovely Valerie."

She smiles warmly. "Nice to meet you."

"And that's the rest of the family behind you."

Confused, we follow his gaze towards a paisley curtain at the back. The Doctor draws it to the side. Inside, five kittens crawl around in a padded wicker basket. They must be very young, still a little unsteady on their feet. Each one has a different coloured ribbon tied around their neck. "Can I?"

"Go on."

"Hello," he coos, carefully picking one of them up. They are purely black, save for a pair of wide, green eyes and white fur forming little mittens and boots.

Admiring just how tiny and delicate they are, I pick up a ginger tabby. My fingers scratch gently at the top of their head. They gnaw happily on the hem of my sleeve. "Gods, aren't you precious?"

My attention is easily caught by the Doctor. A serene look comes across his face, all worries eased by the presence of such sweet and innocent creatures. Moments like this are rare — moments where I find nothing but comfort in his eyes and wonder if this is what he used to be like all the time, back on Gallifrey with his family. A part of me hates that he isn't like that now, that I never got to see him at his happiest, unaffected and surrounded by loved ones. Perhaps it counts as jealousy or even longing. Whatever it is, I wish I could give him something remotely similar one day.

Our gazes meet. His eyes trail from my face down to the child in my arms and the corners of his lips curl up into a soft smile. "How old are they?"

"Just two months," Valerie says, stroking the tabby's fluffy back. It yawns and settles against me with a contented purr.

"Poor little souls, they've never known the ground beneath their paws. Children of the Motorway."

We take another look around the tiny space, not much bigger than the Tardis' exterior. I can't imagine the chaos that will ensue the second they are big enough to walk. This car hardly seems big enough for the four of us, let alone five little ones. "What, they were born in here?"

She nods. "We couldn't stop. We heard there were jobs out in the laundries on Fire Island, thought we'd take a chance."

The Doctor and I exchange bewildered glances. "What, you've been driving for two months?"

Brannigan seems to find our surprise far too amusing, chuckling to himself. "Do I look like a teenager? We've been driving for twelve years now."

"'Twelve years'?" I gasp. "'Twelve... years'?"

"Yeah, started out as newlyweds. Feels like yesterday."

Her dark curls bounce as she shakes her