Graham padded from his bed, fresh from a nightmare. There was no wonder it had struck again, really. Watching someone he had admired so much die in the Punjab had been too much for his desperate, Grace-obsessed brain. He knew from the moment he turned his light off that if he were lucky enough to sleep, it would be painful and fleeting.

The TARDIS had no sense of order but it did have moods. Right now, it was in a bad one. Strips of amber light pulsated in some corridors while he avoided the hungry pitch-black of others. The lights led him on, icy air biting his fingers, his bare feet tingling on cool metal. Deep beneath him, the engine rumbled. He had no sense of where he was heading, only that anywhere was better than his subconscious.

Infinite, the Doctor had called her time machine, as if anything could truly be endless. As if there were another Grace, alive and well, wandering its twisting corridors and searching for him. There might just be, Grace might have said if she were alive. But, equally, she might not.

Grace in the TARDIS. Would she dance around the control room with the boundless energy of a puppy but the wise cracks of a philosopher? Or would her head sink into her hands, the shock of an entire Universe temporarily too much for someone who had always deserved it? Or perhaps she would just have shrugged, saying I always expected to stumble upon something just like this.

Graham was finding it increasingly hard to imagine or remember how Grace would react to anything.

As the TARDIS led him on, a growing, rebellious part of him hoped that she was leading him somewhere to take away the pain, to wrap him in an unknowing cocoon, to reunite him with-

But, no, he ended up on the edge of the control room. It was dim, its usual colours sucked dry so his fingers glowed ghost-like. In the gloom, a figure was doubled over.

Graham stepped forward.

'Doctor?'

'Graham.'

He could barely see the outline of her form. Barely hear her, in fact. That gravelly, voice wasn't hers, nor was the skeleton silhouette of a hand gripping the console edge. But when the figure finally looked up at him, he knew the Doctor was in there, somewhere.

It's okay not to be okay, the Doctor had told Graham once after Grace died. Suddenly, he understood those words had been a promise: he could always come to her for help. Now she was saying it again, breath whistling through her teeth, hunched over the console.

'It's okay not to be okay.'

He took a step back. For long nights after, his reaction plagued him. He should have done what she had done for him: stepped up, showed her that he was just as capable of confronting comforting her as she was him. But instead, he - undeserving, silly Graham O'Brien from some some inconsequential planet - stepped away from the (second) most remarkable being he had ever met.

Doc, he would later imagine himself asking at that point again and again, Are you okay? But instead, he said nothing at all.

The Doctor took a deep breath, sucking in everything, the Universe and more, before taking a few jittery steps towards him and collapsing on the TARDIS steps. She buried her head into her hands, scrunching her hair.

Graham sunk down next to her. The cold was immediate, freezing every bone, every tendon, every blood vessel. Nighttime on the TARDIS. He was still too stuck in a hopeful haze to care about anything more than Grace and searched for the possibilities of her in the darkness: the glint of amber light that could have been her smile; the curve of the TARDIS walls that could have been her shape. He just needed to imagine hard enough-

The Doctor's head tilted so dangerously sideways that he thought she was about to lose consciousness. Graham's hands jerked forward, ready to steady her, but she snapped back upright. He could hear her pain, the rasping breaths of it; feel it, in the tension of her body against his. He thought she might have been crying.

The Doctor looked up at him through sweaty strands of hair as if she had just remembered he was there.

'What are you doing up, Graham? Midnight snack? Oh! If you press that big red button behind the fruit machine lever, jammy dodgers appear. Or maybe that's lizards.'

Even in the corner of his eyes, her gaze burned as if it were under a spotlight and surely she could see into parts of him that he couldn't himself.

'Are you okay?' she finally asked, when he didn't respond.

'I'm fine, thanks. Midnight snack, as you said.'

He looked back into the darkness but could no longer see any traces of Grace. Just the strange, humming shapes of an unknowable spaceship that she had never even begun to know.

How could he tell the Doctor about the nights wishing that he had been taken instead of Grace?

'I know you don't mean to be insulting,' the Doctor said quietly, her voice steadier than before, her breathing slowing down.

'Huh?' he said.

'With the lying.'

'What are you on about?

'Saying you're okay when any idiot can tell that you're not.'

'But I am-'

'Don't!' She held one finger up. In the dust, spotlit from the control panel, her hand shook. 'I watch you, Graham. More than you could know.'

'You can go to prison for stalking.'

'Right now, Ryan and Yaz are asleep, dreaming of other places and times and bodies and realities and physics. But you don't want to.'

'So what? I struggle to sleep.'

'But it's more than that, isn't it?' said the Doctor, suddenly and inexplicably beaming as open and wide as a child. 'We have evolved, you and me, to heal by telling ourselves subconscious stories. Sometimes they are scary. Sometimes they are sad. Sometimes they are so good that waking up is disappointing. But they are all crucial to survival. Memories and stories will always catch up with you in the end.'

'I don't know why you're saying this.'

But he did know. The Doctor was subtle enough not to mention Grace. But he didn't miss the heaviness of the words, what had been left unsaid, her steady gaze on his.

'Now I'm asking again, Graham,' said the Doctor, shifting closer to him. 'Because you're my friend. Are you okay?'

Their knees accidentally touched and neither of them moved away. For some reason he couldn't articulate, he had never felt closer to her: not when they were hugging, not when they gently pushed each other laughing, not when they gripped each other's hands.

The words spilled out before he could stop them. He was overwhelmed by a need to breathe, to admit what he had been thinking, to share it.

'I can barely remember her,' he said, choking slightly. 'Only in- Only in dreams. Yet I am too much of a coward to face them. I just miss her so much.'

'Quite right,' said the Doctor.

'Sometimes I think that she would be so much better at me than this,' he said, his voice sounding papery and weak and unrecognisable. 'You lot wouldn't need to constantly traipse back for that old bloke who needs another sarnie, another explanation or another moment to catch his breath.'

'You've wrong there, Graham,' she said, sounding so dangerous that he forced a weak laugh to dispel some of the tension. But the Doctor didn't smile back. 'So wrong. And I will make you see it. Grace would have seen it in you. She did see it in you. I see it in you.'

Graham was struggling to hold back wracking sobs now. He sucked in a deep breath, willing the tears to stop, but they wouldn't listen to him, and continued to trickle, hot down his cheeks. He wiped his face with his sleeve, pushing thoughts of the morning when he would have to face the Doctor in the daylight.

'How can you see it in me?' he asked, barely wanting the answer. 'How can you see me at all? I'm not even here, Doc.'

'You have carried on, haven't you? Seeing the Universe. You haven't lost hope in it yet. You are sitting right next to me. That counts.'

'You're wrong. I'm so wrapped up in myself that I didn't even ask how you were earlier. You were clearly in pain. You clearly still are. Look at you!'

He stared at the Doctor, the deep purpled bags under her eyes. The small tremors still running through her thin frame. Her sweaty forehead. Through it all, she smiled, took one of his hands in hers, like how one might encourage a child, and reached over with the other to wipe his a tear off his cheek with one delicate finger.

'Didn't ask how I was?' she said. 'Nah, you're not quite that subtle, Graham. I felt your worry, could feel it radiating off you. Kindness that big? Hard to hide.'

'Are you okay, Doctor?'

In a moment of foolishness, or bravery, or rudeness, he reached out with his spare shaking hand to cup her face. He couldn't help it. She closed her eyes momentarily against it and he could feel the wetness of her tears against his palm.

'I'm not, actually,' she said, grinning. 'It's why I'm up, wandering around the control panel, finding puzzles to solve, trying to calculate my way out of it. Just like you. But when I watch you, wandering about at night too, making everything worse… I realise how silly it is. How silly we both are.'

'Do you… Do you get nightmares too?'

'It's the people.' Her eyes were still closed as her eery smile fell, her expression becoming so still that it was if some alien creature was talking on her behalf. 'They die, but they never leave.'

'Who?

'Well, I have quite the graveyard now.'

'Oh.' He felt unbearably selfish for rambling on about Grace, dropped his spare hand from her face, ran it through his hair again and again. 'I'm so sorry.'

'Graham O'Brien, never be sorry for being honest.'

'But how do you continue?' he finally asked.

'For their sake, for your sake, for the sake of the Universe.'

'Very grand, Doctor.'

'For the sake of finding new planets.'

'Don't forget for the sake of seeing Ryan smile.'

'Or the sake of saving more lives.'

'And for the sake of driving a bus again.'

'Each to their own! For the sake of finding out what exactly the round things are.'

'For the sake of…' Graham was starting to giggle. 'For the sake of having conversations like these.'

The Doctor hopped up onto her feet. Her face still glistened with tears, but her eyes shone through. She held out her hand. 'It's time for us to dream, I think.'

Graham felt the urge to scuttle back, to tell her that he wasn't ready to go back to sleep not without a bottle of whiskey, or a sleeping pill, or some magical scientific dreamless tablet. 'Look, Doctor, I don't think I can anymore, not without her coming back.'

The Doctor wiggled her fingers. 'I'm not sure I can either. But I'll tell you one thing, Graham. I've never felt as prepared to face them as I do right now.'

Graham threaded his fingers through hers and she pulled him up.

'True. But I still feel totally unprepared,' he said. 'What if she comes back?'

'Then you know where I am.' The Doctor's hand was smaller than his, but right then it felt so much larger. 'For the sake of the fam?'

'For the same of the fam.'

'For her sake,' the Doctor added, glowing in the TARDIS's warm amber light as she pulled him along behind her and - for the first time in a long time - Graham knew exactly what Grace would say.

For your sake, Graham O'Brien.