'This case is great!' Castle had exclaimed earlier that day with an uncontainable squeak of childlike glee. They'd only been on it a couple of days but it was one of those cases where although it seemed like they couldn't catch a break, it was for the most inexplicable, and Castle thought, alien reasons. Well aliens or secret agents. He had his theories which, he had of course not failed to share with Beckett. He had been teasing her all morning and Esposito and Ryan had been taking bets on how long she would let him.

'Castle there are no aliens!' Beckett told her partner exasperated. 'Just like last time, there is going to be a reasonable explanation for all of this we just have to find it.' She reasoned. Castle opened his mouth to respond but Beckett knew what he was going to say. 'Just because the body is gone...'

'And all the evidence connected to the case?' Castle interrupted with questioning smile.

'Well we still have photos Castle.' She said before noticing Esposito walking towards them with a concerned look on his face 'Espo?'

'The camera's been wiped, there is no trace we even took photos at all.' He told her apologetically. Beckett sank into her chair and looked over at Castle who raised an eyebrow at her with a smile.

'Okay Castle so we don't have photos.' Beckett sighed. Usually with cases like these something would come up. A mysterious person from a previously unknown organisation or a weird phone call would give them a lead so maybe they just had to wait, she thought. That didn't mean she was going to give up though, and she certainly wasn't going Castle's alien theory get too in depth. 'Espo get Ryan and Lanie up here, we need to put our heads together and see what we can remember about the crime scene and our vic.'

'Sure thing.' Esposito said. As he was leaving he high-fived Castle which earned him a disapproving look from Beckett. Castle sat silently waiting for a response from Beckett trying to contain his excitement.

'Okay,' she admitted. 'There is something going on here.' and before Castle had a chance to respond she added 'But not aliens, something will turn up.'

'Disappearing bodies and evidence and our cameras have been wiped? He could be a CIA agent working secretly to develop realistic human Cyborgs. 'Castle started enthusiastically. 'But the Cyborg turned rouge and murdered its creator. They stopped it and its oil leaked out in a trail leading away from the body. They had to obviously would have had to remove the Cyborg and put it in a secure location, which is why they didn't have time to get his body before we arrived. We know he was a mechanic and his ID card was definitely government issued.' He reminded her with a grin. Beckett rolled her eyes playfully.

'Castle, I think even aliens are more plausible than that.' She told him, standing up. 'But that has given me an idea; if we're lucky there might still be evidence at the crime scene from the people that took the body.' She said hopefully so Castle stood up too.

That was when his head started to spin.

He looked to Beckett but she was swaying too, he reached out to catch her but instead in perfect synchrony they collapsed. Darkness encompassed the pair like a blanket putting them to sleep.

Castle woke first still groggy from the unexpected nap. Where was Beckett? Turning round he noticed her still sleeping peacefully at his side. Gently he coaxed her into conciseness. He didn't really want to wake her, she looked so calm in her falsely created sleep, but whatever happened next he knew they needed to face it together.

'Beckett.' he whispered urgently. Beckett stirred a little so he tried again. 'Beckett.' This time a faint mumble escaped her lips.

Kate Beckett opened her eyes blinking in the darkness.

'Castle.' she murmured before sitting up. 'Castle, what's going on?' Castle shrugged, he had his theories but it was too soon to tease her and definitely not the right situation.

'We were at the precinct and then we were ...' He paused, uncertain. 'Knocked out? - and bought here.' He said. Beckett nodded along.

'Where is here?' She asked. Rooting through his pockets, Castle triumphantly pulled out his phone.

'Let's have a look.' Castle shot a smile at Beckett. 'You're right definitely not the CIA, I still have signal.' Beckett meanwhile checked her pockets.

'They didn't even take my gun.' Cautiously checking the barrel she found it still fully loaded. 'It's still loaded. Castle something wrong here.' Castle's expression changed to one of complete bewilderment staring at his phone's screen. 'Castle?' Castle made a few inhuman noises before giving up on speech entirely and handing her his phone. A little red light flashing on the on the screen showed their location. Beckett's jaw dropped.

'If this is one of your jokes Castle this isn't the time.' Deep down she knew it wasn't but there had to be a reasonable explanation. She got up in search of an exit but there were none that she could see. Castle put down his phone and went to help her, the little red light still flashing away; he was quickly distracted though.

'Castle I need light, I think I've found a way out.' Beckett looked round to see where he had gone. Walking up behind him she was struck with awe as she saw what he had seen.

Castle and Beckett stood in the pale glow of the moon looking down upon everything they had ever known. The Earth hung in the sky a sphere of life in the emptiness and everything felt smaller.

'It's beautiful...' Beckett said her voice trailing off in disbelief.

'Yeah.' Castle agreed his voice quiet in awe. They both stood in silence staring out into the space; watching the stars shine and the swirling clouds above their planet. Alone.

KNOCK. KNOCK. KNOCK. KNOCK.

The knocking broke their speechless trance making them jump. Beckett's cop instincts kicked in as she pulled Castle behind her and drew her gun.

'Who's there?' Beckett shouted and despite the circumstances Castle couldn't help smile. 'Castle, focus!' A buzzing sound came from the other side of a nearby wall.

'It's okay, I'll get you out.' came a voice from the dark. 'What's your name?'

'Detective Kate Beckett with the NYPD and Richard Castle. Who are you?'

'Castle and Beckett, Oh you are brilliant! I loved Heat Wave.' The voice complimented.

'Oh which bit was your favourite?' Castle replied happily.

'Not now Castle.' Beckett shushed. There was the sound of a lock opening and a crack of light shone through into the black room. Cautiously Beckett and Castle approached the now visible door which swung open with a creak to reveal a tall silhouette in a tweed jacket with a bow-tie and a triumphant grin on his face.

'Hello!' The stranger beamed 'I'm The Doctor.'