A/N: hello! So this is a bite late... I got all caught up doing nanowrimo. I only wrote ten and a half thousand words- a poor effort, but it was a lot of fun. Anyway, hopefully this chapter will explain everything you've been wondering about. Only one more to go, I expect. (:

The next morning Sam opens the paper to a headline that screams, "MYSTERY KILLER STRIKES AGAIN." Dean reads it over his shoulder, and the two of them quickly decide to grab their fake FBI badges and head on over to the scene of the crime. It's not difficult to find. They just ask around until someone points them to the right street. They duck swiftly under a line of yellow tape and show their badges to the man standing guard at the door, keeping their faces straight as usual.

The crime scene is busy, despite having been open for several hours. Just as with the other murders, the corpse on the floor has been heavily mutilated, though the injuries are different. While the first victim bore a deep gash in their neck and the second had been ripped open from clavicle to groin, this one has bloody holes where his eyes had been and a massive hole in his chest. There are markers around the room, placed near blood spatters, loose hairs, and footprints, though the Winchester brothers know that all 'evidence' will eventually be discounted as the victim's own, or perhaps that of his pet's. All of the doors were locked from the inside when the police came calling, and all windows latched or open only a small fraction- certainly not near wide enough for a person to enter the house through. The man's house, located on a pretty street near the centre of town, is clean (of paranormal activity, that is) but for the sitting room, where the body sits slumped in an armchair and the remnants of a ghost's presence still linger.

The police are stumped, but Sam and Dean already have a good idea of the culprit. The injuries may be different in each case, but the presence of a vengeful spirit at all three crime scenes is doubtless. Of all supernatural beings, they've had the most experience with spirits, so hopefully this case'll be a breeze.

They're conferring quietly in a secluded corner of the room when one of the deputies, a stocky man with pale blue, watery eyes and thin red hair asks for their identification. "We're doing an ID check," he says in a heavy Texan accent. They hesitate, looking at each other. "It's standard procedure," the man says, exasperated. "You must be new."

Sam gives him a pained nod and hands over his fake badge. Dean follows suit. The deputy studies their badges and frowns. He looks at Dean. "Why does your badge say that you hunt monsters? Yours too," he says to Sam. "Is this some kind of joke?"

As Sam and Dean flounder, trying to find an explanation for this strange, sudden turn of events, who should come through the door but the Doctor and his redhead companion, Amy Pond. Sam gapes and Dean stutters while the deputy watches him expectantly, still holding the treacherous badges aloft.

"Agent LaChance, Agent O'Connell, you left your badges in your office. You must have taken those ridiculous fakes we found by mistake!" The Doctor darts up to the three of them, brandishing the badges with a sly grin.

The deputy looks at the strange man with suspicion written all over his pale features. "And you are?"

"Special Agent Smith," says the Doctor, "and this is Miss Pond." Amy waves at them, looking pretty pleased with herself. Dean will later learn that the badge switch was her idea. "She's visiting from Scotland Yard, hoping to help me crack a case."

"Scotland Yard? Are you-"

"Don't tell her, but I'm only helping her out because she's my brother's wife! Haha, but I'm sure she'll be brilliant. She always is." He grins at her, while the deputy stares. It takes them ten minutes to get rid of him, since he insists on closely studying their identification, but in the end, after a few not-so-subtle hints, he takes his leave.

"Whew!" says the Doctor. "That was close. Well, not really. I knew exactly what I was doing, but you two, taking the wrong ones. So silly, I-"

"Perhaps you'd like to explain to us why you swapped our badges," Dean interrupts tersely.

"Alright, fine." He takes the badges out of his coat pocket. "This is psychic paper. The person you show it to will see whatever you want them to see. Obviously you had no idea what they were so when you showed them to that deputy your mind wandered and the paper fixed on your, er, real profession. In other words, it showed you for what you really are, not what you wanted them to believe."

"That's... amazing," says Sam, aghast. He takes one of the badges and shows it to Dean. "What does it say?"

"It's says you're a professional tiger trainer with a degree in making pottery..." Dean says, laughing.

"Can I keep this?" Sam says, his smile wide.

"Oh yeah, sure, I have plenty in the TARDIS."

The Doctor feels someone grab his arm and he starts, turning around to see Amy, staring at the body with a frightful shade of grey and green on her face.

As he helps her out of the room, to the amusement of the watery eyed deputy, he calls back to Sam and Dean, "I'll see you outside! And don't think of trying to lose me, because I'll find you."

ooo

"I'm sorry Doctor," Amy says. She's sitting next to him on the curb, hugging her knees tightly to her chest. She still looks green, though not nearly as much as she did before.

"Don't apologise, Pond. It was grisly in there." He looks sad and pale, and a little apprehensive. Her tone suggests that she's not done. He's right.

"No, not for that," she sighs. "I've been thinking about everything that's happened since we got here, and I don't know if it's something I did or not, but it must be, because you barely speak to me now and I feel... I feel like I'm burdening you." There are definitely tears in her eyes. He's not sure what's worse; the tears, or the way she can't seem to look at him. "I keep having these weird dreams and sometimes I hear you muttering in your sleep. I want you to tell me what's going on, Doctor, please."

"Of course," he says. " Of course you do..."

She scuffs her shoes back and forth among the wet leaves in the gutter while she waits for his response. It's autumn, but the air is still warm, though humid. The whole street reeks of the typical American suburb. You would never guess that someone had died violently in the house behind them were it not for the police cars and the curious bystanders.

She looks up and sees him blinking at the ground, his mouth opening and closing with no words coming out.

"Why don't I help you?" she says. "Tell me why you can't look at me right now. Tell me why you never tried to stop Rory from leaving. Tell me why you're intent on helping those nutcases on this horrible job of theirs. And please, please tell me what happened that still makes you cry out in your sleep and jump like an electro-shock patient when you wake. I can't stand not knowing anymore, it's driving me crazy!"

He speaks so soft she can hardly hear him. "You died, Amy. You died and I couldn't bring you back. You weren't even... you weren't just dead, you were gone. Lost. And I almost forgot you. Rory forgot you. He left me." Tears start to fall down his cheeks, and he wipes at them frantically. Amy can't move, she can't breathe; she can only stare at him as he tells what she's needed to hear for so long. "We were on a case, just the usual stuff, trying to stop a nest of Sontaran from blowing up London, but they took you. I wasn't paying attention; I was trying to shut down their missiles. It was a tricky job. I had to do it from a space shuttle. Anyway, they took you and... they executed you. And then they shoved your body into a crack in time so you never existed and I almost... I almost forgot you, Amelia Pond."

She still can't speak, so she takes his hands and smiles, and finds her words in his eyes. "Thank you for remembering me, and thank you for bringing me back, Doctor." And she leans forward and kisses him, just lightly, just a little, while their tears fall and gather on the pavement below them.

"There's more," he whispers. "I tried to get you back by myself, even though I knew there was no way." His words are so quiet she's straining to hear. "One of the Sontaran shot me, stopped one of my hearts."

"So... you only have one now?"

"Yes. I'm okay though, "he says, trying to smile, reassure her. "Just can't run so much. Maybe after this I'll go to the hospital on New Earth X14, see if they can do anything for me."

She sits in silence for a moment, then realises he still hasn't told her how he bought her back. She asks him, and he says, "I had to make a trade to bring you back. With a demon."

"What?" she pulls back from him, but he holds her hands tight.

"I traded my soul for you, Amy, I had to."

"No," she says, "no you didn't! That's your soul, you need that."

"The demon gave me time, to spend with you."

"You don't want to waste it on me."

"Oh, but I do. I really do."

She forgets what she wanted to say next because the words demon and soul and dead are swirling around her mind. "I don't understand," she says. "If I died, why was everything so... so normal, when I got back?" She sees his face and takes it back, "It's not normal. It's completely different, but why don't I remember anything? Don't you think I would remember dying?"

"You would think so," he says, as he rubs her fingers between his, her hands still in his grip, "but I'm no authority on cracks in time. They're an enigma, even to me. I'm guessing that's it a side effect of the fact that you were essentially erased and then bought back again. It's bound to be a tricky process for whichever magical forces the demon had working for him."

"What was it like, dealing with a demon? Was he... scary?"

"I sure hope so," she hears. The Doctor jumps up and twirls around, and Amy follows suit. There on the pavement is-

"Crowley?"

"Correct. Well done, Time Lord," says the man. Amy notes his black suit and dark eyes and the way he's looking at the Doctor. It looks as if he wants to eat him. Then his eyes flicker to black and back again and she flinches, stumbling back. "Did you miss me?"

"Can't say I did," says the Doctor.

"Who is he, Doctor?" Amy asks, gripping his arm tight.

"This is Crowley."

"The King of Hell," the man quips.

"He's a demon."

"Is he... is he your demon?"

"His demon? Oh honey, I don't think so." His gravelly voice grates at her like fingernails on a chalkboard, although she has to admit that it's rather pleasant, in a strange way. She shivers and forces the thought out of mind, trying to remember who she's dealing with.

"If you're a demon," she says, "why do you look like that?"

"What, like a human? I know, isn't it disgusting? I don't understand how you people put up with it." He gestures down at himself. "This is my meat-suit. It's much more presentable attire for when I'm on top. Down below I can be very, very scary."

"A meat suit? So you mean... that's a real person? Is he still in there?"

"A little, yeah, but I wouldn't dwell on it too much, dear. All he ever does now is sleep, anyway."

"This is insane," she says. "I'm going back to the TARDIS." She doesn't look at either of them or policemen gathered on the front lawn as she walks away.

"Why are you here?" the Doctor says quietly, crossing his arms.

"Oh, I'm friends with the Ken dolls that are currently sniffing around inside. You might have seen them, they're the ones-"

"I know. Sam and Dean Winchester, the hunters and part time FBI agents. We've met."

"Oh, you have been busy! Tell me, how long has it been since we made our little deal?"

"About a week."

"Really? That is fascinating. So you really are a time traveller..."

"You didn't answer my question, demon." The Doctor is still speaking quietly, and it's starting to unnerve Crowley. He can see it in the way he's begun to fiddle with his fingers, and the way his eyes are darting back and forth, from his bow tie to his face to his shoes to his hands. He's searching for anything that he can take advantage of, but he's not finding it. Infuriatingly enough, the Doctor is the most impenetrable fortress of a man that he's ever met. "Why are you here?"

"I thought I'd pay you a visit. Oh, that and the fact that some of my demons are wrecking havoc in the next town over. I have a whole horde of naughty demonic children- it's a little difficult to keep track of them all at once."

The Doctor stares at him and says, "With every new thing that you say, I have about a million more questions."

"Talk show later, Time Lord. I'm busy." And he's gone, leaving the Doctor standing alone on the pavement, looking through the spot where the King of Hell used to be.

At that moment Sam and Dean come out of the house, talking with their heads together and so distracted that they don't see the Doctor until they're nearly on top of him. Sam straightens his tie and looks at him as if he's never seen him before. "You're still here?" he says.

"I am," the Doctor says, crossing his arms. "The case is still open, isn't it?"

They look at each other. Sam clears his throat. "Uh, technically, yes. Although now we know what it is and we know how to kill it."

"But?"

"We still need to find it."

"Well, I can help you with that. I think."

"You can? How?" Dean says.

"...Perhaps tell me what is it that's been killing people first?"

"Right," says Sam. "We're about 99 percent sure that it's a vengeful spirit. They're usually a person who died with unfinished business, and most of the time we can get rid of them just by burning their bones."

"Come back to the TARDIS with me. I have lots of cool stuff in there. Something's bound to help us find him. Or her." And he's off before they can say anything, whirling around and striding down the road in the direction of his time machine. Sam shrugs at his brother and follows. Dean sighs and does the same, all the while thinking that despite all they've seen, this is definitely in the top ten for weirdness.

When they step through the TARDIS door Amy is leaning on the console with a huge mug of tea cupped in her hands. She looks at them in that incredulous Scottish way that she has and says, "What are those two doing here again?"

"Amy, Amy, be polite to our guests! We're going to help them find a ghost. Can you pull that screen behind you down? Good. Is there any tea left?"

"Yeah, there's loads," she says. "What's the screen for?" she calls after him as he runs up the stairs to the kitchen.

"Just press the purple button! And then the green one!"

She does what she says. The little screen goes white, then comes up with an hourglass while the words "loading current location" flash underneath it. In a few seconds it has the exact city pinpointed, and the words change to "searching for alien activity". She hums to herself while she waits, and Dean and Sam exchange looks behind her back. The screen starts to beep at the exact moment that the Doctor emerges from the kitchen, carrying a pot of tea and three mugs on a tray. He pours Sam and Dean and himself each a cup while Sam grins and Amy hums. Dean still looks out of sorts in the time machine. He fingers with the butt of his gun, but stops when he sees the Doctor eying it disapprovingly.

The screen gives out two long beeps and the Doctor turns the screen to face him. "Aha!" he says. "See, there's some activity here and... a lot in the next town over. That must be what Crowley was talking about-"

"Wait," Sam chokes, almost dropping his mug, "Crowley's here?"

"Oh," says Amy, "you know the scary demon?"

"We've met, yeah," says Dean. "He's a total dick, in case you didn't notice."

"What did he do to you?" Amy asks.

"He, uh..." Sam looks at Dean, who shrugs. That seems to be the go-ahead, because Sam says, "He tried to open purgatory and got one of our closest friends jumped up on souls then killed in the process, and now we're sort of in the middle of a hunt for some really nasty creatures. But really, we don't have time to get into that. We have to find the spirit."

"And burn his or her bones."

Amy says, "Does that mean...?"

Dean nods. "Yep. If all goes well, you two will be helping us dig up a grave!"

The Doctor grins and says, "Can't say I've ever done that before."

Amy looks slightly less enthused, but she drains her mug and grabs her coat all the same, saying "Let's go then, boys," before stepping out the door without so much as looking back to see if they're following her. The Doctor almost runs out, and the Winchesters follow, albeit much slower. Sam calls out to ask why they can't just use the TARDIS to get there, but the Doctor, from ten metres ahead, says that if they want to be accurate they should use the car.

The sky is darkening when they emerge, the air humid and the breezes few and far between. As Sam steps out, behind Dean their new companions, he notes the clicking of cicadas and the red of Amy's hair flying in the wind. Dean saunters along beside him as they walk slowly behind the others to the car, which they'd parked right outside the victim's house. When Sam and Dean reach it Amy and the Doctor are already there. They're talking, but stop abruptly when they see the brothers, exchanging meaningful looks. The Doctor looks angry and Amy slightly sheepish. Sam doesn't inquire as to why, just opens the passenger door and gets in.

It's only five minutes to the spirit's location; a small cottage near the outskirts of town, set back from the road at the end of a gravel driveway. Dean parks at the mailbox and they get out and walk up, Sam and Dean with guns and Amy and the Doctor with iron bars that the brothers supplied for them. Amy starts to sweat as they draw nearer. She can feel her hair sticking to her forehead and goose bumps on her arms and legs. She's expecting another slaughter.

What they see when they reach the porch isn't what they'd expected at all. The door swings open as Dean puts a foot on the first step, and standing there in the doorway is the King of Hell. The demon Crowley.