The darkness was heavier than anything she had ever felt before. Wrapping her like black velvet, it blocked the sounds trying to force their way past. Voices she knew. Cries.

"Stay with me, ok? Kate? I love you. I love you, Kate."

"Hang in there, girlfriend. You are not allowed to do this. Jave – get that ambulance here now!"

A drifting, easy feeling that would be so easy to let go. Just fall down into darkness.

"Katie? Hon? If you can hear me, hang in there. Dammit, Katie, you didn't give up on me all those years ago, you're damn well not giving up now."

Deep and wide and beckoning, so very very inviting, calling her to rest and leave this noisy, bright, pain-filled world.

"Kate, please. Please hold on. Don't go. I'm sorry. I'm sorry I was the fool and the monkey and all those things. You were right. Even if it's just to walk away, come back to us. I love you. And I can't bear to lose you. Not now."

She looked around the grimy corridor, the lino worn from years of sensible, solid shoes walking back and forth. The door ahead bore the words "Criminal Investigation Department" in chipped letters on a bakelite sign, and a thin waft of smoke curling out. Kate Beckett shook her head to try and clear the confusion she felt, stepped up and opened the door.

The scene in front of her looked like the first police station she had worked in. Grimy stained desks loaded with paperwork and half-filled coffee cups were crowded into the room, with battered chairs tucked under or lodged beside them. At the back, the sound of yelling blasted out of a private office with venetian blinds on the windows hiding the occupants.

It took a minute for Kate to realise what was odd. It wasn't so much the cigarette smoke – smoking had been banned in the NYPD for a long time but people still snuck into stairwells or hung around the backs of the precinct buildings, and the smell tended to permeate. No, it was the contents of the desks. Typewriters. No computers. Not one screen or keyboard, and not a mouse to be seen.

Wait. She was wrong. There was one, sitting on a desk, quietly nibbling a forgotten cookie - but it was the wrong sort of mouse. She grimaced, and headed towards the noise.

At that moment, the noise came to her. The door was flung open with a resounding "crash", and several men slunk out with an air of having been read the riot act. They pushed past her and headed to the various desks, while the heavyset man standing in the office doorway looked her up and down as if she was some sort of alien life form. Or perhaps a cookie-stealing mouse.

"Oi. You. Get your skinny backside into my office pronto, before I drag you in myself."

His accent threw her. You just didn't expect to hear a broad Mancunian drawl in the middle of an NYPD Homicide division. Or any other police station.

"Me?"

"Yes, you. And don't you be getting your knickers in a knot either, Miss Fancypants."

Kate drew herself up to her full height and gave him the patented Beckett deathstare, but he merely gestured her in with a look of total disbelief and muttered something about liars and the weirdos. She shrugged and went into the office.

He pointed her to a chair and perched himself on the side of a desk. Kate still had trouble thinking straight, and sat down hard, rubbing her head with her hands.

" Hard night last night? Pull your bloody head out of your backside and explain what you're doing swanning into my department looking like you were going to some swanky poof-fest."

"I beg your pardon?"

"Your name, sunshine. Your name, your rank, and maybe why the hell you're here?"

She looked around the room, trying to find something that made sense to her. The fuzzy thermal paper faxes with badly-scanned photographs taped to the glass walls were incredibly crude, as if they had been made with some sort of ancient printer. And the torn page from the newspaper … Who the hell was Samantha Fox and why was there a topless photo of her on the wall? Kate got up to look more closely at the page, which had headlines about the Hitler Diaries and something about Prince Charles.

She was just looking for the date on the page when the phone rang beside her. Again, there was something odd ... The man picked it up, barked out "Hunt", then listened for a while. Kate finally spotted the date as he hung the phone up.

1983? And that paper looks new! What the?

"Right, well, that's a mucking great stuff-up. Just let me check, my pretty. Who are you?"

"Detective Kate Beckett, NYPD."

"And in the wrong bloody place and all. I'm DCI Gene Hunt, and I was hoping you'd be calling me 'guvnor', but it seems the powers that be got things wrong."

"Wrong?"

"You were supposed to be transferring for some special duties, but they sent you here instead of New York. And now the guys upstairs have completely stuffed it, and told me to send you home."

"Home. As in New York?"

"Well, sort of, yeah." He lowered himself from the desk, grabbed a camel coat off a chair, and started heading out. Then he looked back at her.

"Coming?"

She hopped up and followed him into the main room, where phones were ringing and low murmured voices sounded like every Homicide division she had ever worked in – except that the rings were odd and the accents even stranger. Gene had reached the far side of the room and headed into the corridor, and Kate hurried to catch up with him.

"What is this place?"

"This? This is the world's greatest cesspit, Manchester's own CID. Only the best get to work here." He led her to a battered lift, its doors as grimy as her own office ones were mirror-like. "And I don't doubt that you're pretty good where you came from, but you can't stay. This time, anyway." The lift door opened and they got in, Gene pressing a button low on the panel. The lift doors shut and the lift itself lurched down in a fit of stops and starts.

"Blame your boss."

"I'm sorry?"

He turned to her and smiled regretfully. "Your boss. He's got some serious string-pulling powers, even here, and he just rang to say you're to go home."

The lift shook again and the lights flickered as Kate's head started to pound again. "Wait. What? Which boss?"

And as the lights went out fully, her companion laughed. "Captain Montgomery. Sounds like a right tosser, but he says you're needed back at the station. Called it a castle or something."

Darkness. Falling. Then a great gasp, and breathing fire and sand and gravel and things that you're not supposed to breathe, surely, but breathing all the same. Beeping noises and a bright light and voices around her.

"She's breathing by herself. Oh thank god." A familiar voice. But cracked, worn, as if it had cried and ranted for a week and not slept.

"She'll make it now. I'm sure of it. Kate? Can you hear me?" An unfamiliar voice, calm and confident and very professional. "You call her. She'll hear you."

"Kate?" The first voice again.

She opened her eyes, the brightness painful like a summer sun seen full on.

"Rick."

And she closed her eyes, this time just to sleep.