He was watching from the doorway, fairly certain she was aware of him, but keeping still and silent anyway as she preened in front of her dresser. Three mirrors of course. At first he'd found it hard to understand why she spend so much time there now, but then eventually she had explained, adding that as a man she didn't really expect him to 'get it.'

But he sort of did. Understand her fascination with her features. He did it himself for a while after each regeneration, after decades as one man, suddenly, on the surface, another. Change. He would change and have to relearn his face, his expressions, his body.

Clara hadn't changed even when she wanted to. For four hundred years her appearance remained the same. Her hair never grew, her nails remained the same length, she'd tried dyes and cuts and even tattoos but nothing remained longer than a beat of her heart. Now she brushed her hair out each day and noted its length had increased. Now she nurtured her nails and wore different polish and cursed if one broke. It was intriguing and new, just like the other possibilities a living life could offer. She was embracing it wholeheartedly, bravely, just like he knew she would. As always she was stronger than him, more adaptable.

He saw her glance up into the central mirror.

'You standing there again?' she teased, 'You're becoming creepy. I'm only brushing my hair.'

'It looks longer,' he said as it fell from her brush across her shoulders. It looked a little like it had when he had first met her, all that time ago.

'It is,' there was pride in her voice, 'grown a good couple of inches maybe? I was thinking of colouring it, just a shade up, more golden, what do you think?'

'Do you really expect me to have an opinion on that?' the Doctor sighed as he crossed the room and took her hair in his hands. Gently he ran his long fingers through it, releasing the smell of her shampoo into the air. Clara purred a little and he carried on, watching her blissful face in the mirrors, three Clara's, all of them his. He felt her presence calm him from the thoughts that had kept him awake all night. 'I suppose you want me to take us to some sort of Space Hairdresser?' he asked lightly.

'Yes please.'

His hands continued to work.

'In the meantime just put it in a ponytail,' she held up a band. He didn't yet want to relinquish her hair but she raised an eyebrow at his hesitance to encourage him on. With a small protest he wound her hair and flicked the band back and over, about to release her when something caught his eye.

'What?' she asked when he paused. He leaned over her and appeared to carefully extract something from the top of her head. 'Please tell me I didn't pick up some weird alien parasite on that last trip, I mean I don't feel itchy but…'

'You have a grey hair,' he said.

A pause as conflicting emotions passed over her face. 'Really!?' she asked, glancing down at her hands. Then she laughed lightly, 'well its four centuries overdue, about time I sprouted one. Just pull it out. No big deal.'

'You aren't alarmed?' he asked carefully after seeing her reaction. He'd seen the fuss ordinary humans made about hair. Baldness, greyness, it could throw them into quite the panic.

'Of what, one hair? That's what dye is for,' she very deliberately caught his eye to reassure him but her jollity seemed forced and he sensed something in her speech which worried him, a tone he couldn't identify but which felt like a lie. As per instruction he plucked the hair and she reached up to take it, study it. She drew it out to its full length between her fingers and looked at it accusingly.

'Space hairdresser will sort you out, and any buddies you might have,' she said narrowing her eyes, but the other muscles in her face were giving her away. She dropped the hair to one side of her and returned to her ministrations at the dresser with a less steady hand.

Age.

It was not something she'd had to deal with before. She had been in prime condition since being Extracted, frozen for four hundred years. Once rescued time had started again for her and her body but it had only been a couple of months, not long enough yet to see real change in her body. This was the first sign, a single grey hair. Time used to pass without leaving its mark and now here it was reminding her that this had changed, that every second took a second from her lifespan. She'd been alive just a few weeks and Time was very deliberately showing its presence.

'Grey's not so bad,' she muttered when the Doctor did not move, 'You've got lots of it.'

'Most versions of me do, I like to think its distinguished.'

'That's not true, you were gutted to be grey again.'

'Well I got used to it,' he admitted.

'Space hairdresser,' she said catching his eye again. 'We need to go there.'

'What now?'

'It's been upgraded to an emergency,' Clara explained. 'And it will make me happy,' she wheedled. 'Go, programme co-ordinates, I'll be there in a minute.'

The Doctor sighed. This was not how he had planned the afternoon, researching instead a wonderful far flung and recently discovered planet with intriguing cave systems and venomous butterflies. However, he had been around Clara long enough to know about her innate vanity and also her stubbornness and as such knew he had little chance if he protested, especially now the grey hair had been spotted. He chewed on his thumb as he left the room and hesitated in the corridor to look back. He saw her lean closer to the mirror, checking her features, her skin and her eyes and her hair.

It was only one grey hair, he told himself, it meant nothing. Clara disagreed.

She combed her fingers along her parting, hunting, gnawing on her lower lip as she focused. After a minute or so she sat back, her expression no less worried and from where he stood he could almost feel her anxious heartbeat. The Doctor's own sped up in sympathy. He knew the significance of the hair even if he tried to deny it or smother facts with humour. It wasn't her vanity, it was fear. Clara had been reminded that she was aging, and Clara was scared. So was he.

He pushed his thoughts aside again just as he did every night when he lay awake watching her sleep; watching each breath fill and leave her body, imagining it as nature's countdown. He buried the nagging ideas and went to the console room as instructed, he knew a good place to go, she could have a whole makeover if she wanted to, if it would make her forget what she'd just realised, if they could both just continue on as things were without acknowledging Time.

The Doctor found himself loitering outside a café in what could be described as the fashion capital of the quadrant they were currently parked in. He nursed something approximating to coffee at a rickety table opposite the boutiquey Space Hairdresser Clara was visiting. She'd been in there for hours and he could have just hopped forward in the TARDIS to pick her up but he needed the stillness, the thinking time. He'd tried to ignore the thoughts the grey hair had given rise to but when they refused to budge he decided to just allow them to run free for a while and hopeful burn themselves out.

They had been so happy. When Clara's pulse returned it was all about having a future again and being together. Admittedly adjusting to her body functioning after a form of stasis for so long had been difficult and not just physically. They both knew there were implications for her lifespan but neither wanted to address that. The days were about visiting places, eating good food, making love and absolutely not putting a dampener on any of it by thinking about death, mortality, age, infirmity or anything else along those lines.

But he had to didn't he, as the one who would be left behind? He had to think about all of it, again. He'd already been through the loss of Clara once and look what that had done to him. It would never survive it twice. Or would he? Would being with her give him the strength? Now that he had her, now that he could tell her the things he needed to, would he be able to cope with loss the way everyone else seemed to? Could he bear to find out?

And Clara. Wise Clara who at first accepted she was a human with a human lifespan, taking risks and bravely facing the Raven. Clara who then adjusted best she could to immortality she never asked for; now she was mortal again. Her world tipped over and then tipped again. She thought she had hundreds of years, now she had around sixty. She'd spoken to him of her confusion as they skated on a frozen pond on a trip to Victorian London. Nothing was simple, not for either of them, and neither knew what was for the best.

The Doctor put his head in his hands and let his fingers scratch circles on his scalp. What was for the best? The thing that hurt them least? There were ways to be immortal, he knew that, but was that just his own desperation talking. Would Clara grasp at it when her aging body let her down? Was it ever right that she should live longer than any other being? He heard himself groan in frustration.

'Coffee that good?' Clara asked from where she stood above him. He looked up to find her resplendent, hair in soft wide curls, more golden than before but retaining her authentic deep brunette. She glowed.

'You look beautiful,' he said.

'Correct thing to say,' she sat down opposite him and smiled, 'I feel better, sorry about before, all panicky about a grey hair. I mean one grey hair.' She shook her head in disbelief.

His own smile twitched in return but couldn't quite make it, 'Its fine, I understand.'

Clara pursed her lips and fiddled with the table top, drawing her nail along a groove in the surface. 'So, let's have an adventure,' she said out of nowhere.

He raised his eyebrows. 'What?'

'We've been travelling for a couple of months but we haven't got ourselves into trouble…'

'That's a good thing, we're keeping our heads down remember. Reapers. Time Lords. Lots of enemies for the pair of us.'

'There's only so much shopping and sunbathing I can do,' she said in a pleading tone.

'No Clara, we have to be careful, we've upset a lot of people Extracting you, stealing a TARDIS, running away. Time itself is coming after us…'

'You're so dramatic, Time isn't a conscious being, it hasn't decided to come get us.'

'Reapers are conscious, and what we did, even though the paradox is sealed up they are angry enough to find us elsewhere.'

Clara tapped her fingers on the table and squinted around the area they sat in, a little square, a few peaceful aliens going about their business. 'I miss the chase,' she said, 'The adrenaline, I've not had a good shot of adrenaline since I got my heartbeat back…'

'Clara…' he said warningly.

'Oh come on, just a small adventure, you love it, you're just being all overprotective again and we agreed we wouldn't do that this time. I make my own decisions…'

'Clara…'

'… and you make yours, but one thing I know about you is you never sit so still for so long….'

'Clara!' the Doctor hissed suddenly. 'Be quiet and look at me, at me Clara, not over there.'

'What?'

'You may have just got your wish.'

'Clara's face performed an odd expression between excitement and concern.

'You're right I don't usually sit so still so long, and sitting out here may have been a mistake,' he drew his sunglasses out of one pocket and casually slipped them on, his gaze moving to behind Clara where an alleyway looked particularly dark and foreboding.

'Why?' Clara whispered.

'It's allowed someone to send for backup, someone looking for us I suspect.'

'What kind of back up?' Clara asked.

'Judoon,' he said shortly and inched his chair back a little way. Clara's face had gone pale. 'You remember where the TARDIS is?' he asked.

'Yes, but I'll be with you, right?'

'That's the plan,' he said taking her hand, 'but we might have to split up, whatever you do don't waste time looking back or trying to take smart short cuts, just keep moving.'

'Ok,' she said, bracing herself.

'Ready?'

'Yes.'

'Run!'

They shot up from the table in unison and began running down the length of the long and cobbled road to where the TARDIS had been parked around a mile away. To each side of them aliens moved hastily out of their paths while those who were to late were shouldered and bumped. A few swore at the couple but then changed their tune when then Judoon came thundering down the street in military formation. The Doctor rounded a sharp corner, and felt Clara's grip on his hand slip a little. He broke his own rule and looked around to find her just beside him and keeping pace but struggling to do so, more than he had ever seen her before. Her breath came almost too rapidly and she was flushed and rasping. He felt sweat in her palm and tugged on her to keep up. Clara stumbled and fell forward a little forcing him to stop briefly and get her upright while the Judoon soldiers closed the gap.

'Clara! What is it?'

'I… I… don't know…' she heaved out, 'Can't… keep… up… breathless.'

'Don't talk, run,' he ordered and pulled her forward again, drawing his sonic screwdriver out of his pocket should any of the Judoon get close. This was standard stuff, a chase to the TARDIS and an escape. Normally she would be ahead of him, fast on her short legs, something he could never understand, but within seconds she was trailing again.

The march of the judoon was relentless and they were catching. Mercifully the TARDIS was in sight and opened her doors to them immediately even though there were still a few hundred yards to close. Clara was really struggling now and the Doctor paused to scoop her upwards with one arm while propelling both of them back towards the ship. In his other hand the sonic sent blasts towards the soldiers, stunning and temporarily staggering them, slowing their progress for a few moments at a time.

At last they got to the TARDIS and Clara stumbled over the threshold while the doors banged shut and the Doctor quickly punched escape co-ordinates into the console. The ship entered the vortex and silence fell over the console room.

The sound of hard breathing from the steps up to the balcony attracted the Doctors attention. He wiped his own brow of some minimal sweat and sat next to Clara.

'Are you ok?' he asked.

She was leaning with her head down between her knees and when she spoke her voice croaked a little, her breath still ragged.

'I.. don't know,' she admitted slowly getting control of her breathing. Her head came up and he could see how red her cheeks were, how the sweat gathered on her top lip and beaded her forehead. Her newly coiffed hair stuck to her face and neck. 'I never get like that that,' she said, 'I've always been able to run.'

'And you wanted more adventures?' the Doctor said. She smiled in response but remained looking worried.

'Maybe I just got too used to not having to breathe?'

'Maybe.' His voice was flat as he struggled to hide his concern.

'Maybe my adrenal glands haven't woken up yet.'

'Possible.'

'Everything else is working OK.'

'We thought so,' he agreed.

'Is this to do with the Extraction?' she asked suddenly, 'Have I lost all my fitness levels?'

'You were frozen, nothing should have deteriorated,' he explained.

Clara passed a hand through her hair and tried to smooth it into place again. 'Everything aches,' she said, 'My legs were like lead and no matter how much I wanted to speed up I just didn't have any strength. Now they're like jelly. What could it be?'

'Virus? Something contagious?' The Doctor chewed the inside of his cheek with anxiety. 'It could be all number of things I suppose,' he said, thinking out loud, 'It's possible that maybe the last two or three months have been enough for your fitness to decline as an aftereffect of Extraction, we don't truly know how it works. You won't decline while frozen but it could go twice as fast once you're out.'

'Well I don't feel ill, so I think virus is out. And I guess I haven't exactly been hitting the gym,' she said, 'The only work out I get is…'

The Doctor raised his eyebrows and silenced her before he smiled a little shyly. 'You flatter me,' he said. Clara took his hand but he could feel the tremble of her tired muscles through it. He frowned again. Why had she been so out of condition?

She was clearly wondering the same thing. 'Wait…' she said eyes widening, 'If my body was doing that, losing its fitness twice as fast to sort of make up for the frozen time, would other things be like that too, like…'

'Like what?' he asked still only paying half a mind to what she said as he tried to work out the question.

'Speeded up. Like aging,' Clara said. He turned to her slowly as she went on, afraid to look in her eyes, 'I didn't age and now maybe I'm ageing too fast? Hence the grey.' A look of abject horror crossed her face and the Doctor felt his hearts contract.

Maybe. It was a possibility. Long term stasis of any kind could cause these types of problems, especially in space. Why should Extraction be different? His thoughts rambled on, trying to find reasons it wasn't that way and coming up with very little.

'I doubt that Clara,' he said. 'It was only one grey hair. I don't think it's that at all,' her posture relaxed a little but he didn't think she was entirely convinced.

'Phew… that's good to hear,' she said, 'It's been bad enough with the grey hair today.' Her voice was brittly upbeat. 'Ok, shower time.' The Doctor watched her pull herself up by the banister of the steps and make her way down the corridor to their room. She was rubbing at her back as she went. Clara almost never complained of muscle aches and pains. She didn't need to lever herself up from the stairs.

Clara. Clara, Clara. What was going on? What had he done? Had he Extracted her and then saved her from the Raven again, only to cause more problems? Given her her heartbeat only to curse her with accelerated aging? How accelerated? Could it be stopped? Was Time going to exact revenge for his meddling and take her from him early again? He knew from experience how difficult time was to defy. If a person was to die young there was very often no way to change that. If Time didn't want Clara Oswald to live it would surely find a way. It was already angry with him, now it was lashing out in its vengeance.

The Doctor sat on the step with a sick feeling in his guts and his mind racing. It was a fear he hadn't felt for centuries and one he associated only with her. He had to calm down. He didn't have enough evidence. A grey hair and a lack of fitness did not a disaster make. Yet. He shouldn't worry her. He would just keep an eye on things, do some subtle research. Watch for any other signs and keep her safe. He began a mantra in his head, tried to focus and calm himself.

It would be OK. If there was something wrong, he could fix it. If Clara's life was at stake, he could save her.

He could save her. He had to save her. He was the Doctor and he saved people.

Especially his Clara; he still had a duty of care.