"You know, Doc," Dean said as they touched down in a different area of London. "I'm a pretty decent mechanic. I could take a look at the engine for you, see if we can get rid of that grinding noise."

"River says he leaves the emergency brake on all the time," Amy said.

"Do not! River's only part Time Lord, she doesn't know how to fly the TARDIS," the Doctor said, casting Amy a hurt look. "Anyway, Dean, it might be a bit above your…ahh…particular skill set. Ever work with a vortex manipulator?"

"A what?"

"Time flux capacitor?"

Dean frowned. "You stole that from Back To the Future."

Sam laughed as he picked up his jacket from where he'd flung it over the back of a seat. "You're just afraid the whole thing will shake to pieces around your ears, Dean."

Dean shot him a glare. Sam grinned as Amy burst out laughing. He could get used to being around other people, ones who were willing to tease Dean along with him.

"Oi. Don't listen to them, Sexy." The Doctor patted the console, then hurried down the ramp leading to the door. "I still believe in you."

"Sexy?" Dean said, pulling on his jacket. "You call your time machine Sexy?"

"You call your car baby," Amy pointed out.

Dean immediately looked at Sam.

Sam held up his hands. "It's not like you try to keep that a secret or anything."

Dean rolled his eyes and turned to Amy. "That's perfectly normal. Lots of people name their cars."

Hr shouldn't, he really shouldn't...but Sam couldn't resist a jab. "Usually balding men in a mid-life crisis."

Dean punched his shoulder. Sam punched back and ducked as Dean went to grab his hair. "Uh uh. Off limits, remember?"

Dean sniffed. "Fine. I don't want that strawberry-scented conditioner crap all over my hands anyway, Samantha."

"Jerk."

"Bi—"

Amy pushed them toward the door. "You do realize the Doctor's been gone for over thirty seconds, right?"

Sam ducked as he stepped out of the TARDIS. They stood on the corner of a busy street, tall apartment buildings rising up around them. Rain spit and spluttered from the gray sky, making Dean grumble under his breath and pull his jacket over his head.

The Doctor stood across the street, practically dancing a jig in front of a small doorstep topped by a black door. Sam squinted at the letters as they hurried across the street.

"221." He looked up at the street sign. "Baker Street." He grinned and punched Dean's arm. "We get to meet Sherlock Holmes. This is awesome!"

Dean pinched the bridge of his nose between his thumb and forefinger. "Awesome. Since when did my little brother become such a fanboy?"

The Doctor rapped on the door, then looked over his shoulder at them. "All right, you lot. Let me do the talking. Just smile and nod. Oh, and don't wander off!"

"Wow, yeah, you haven't said that before," Dean said.

"It's one of his rules." Amy scrunched her face. "He has a lot."

The door opened. Sam looked over the Doctor's shoulder. A petite woman stood in the doorway, smiling and fingering the collar of her dark purple dress.

"Ah, hullo!" the Doctor said, turning his attention to her. "Might we come in for a sec?"

Dean elbowed Sam in the side. "See? The Doc has rules. Now tell me I'm crazy to have rules."

"You're crazy to have rules. And you realize you just relegated me to companion status, right?"

Dean grinned broadly and followed the Doctor and Amy into the hallway of the flat. Sam crowded in after him, narrowly avoiding Amy's toes. A staircase rose immediately in front of them, and the landlady stood off to the side beside a door and a staircase leading downward.

"Are you all here about the flat?" she asked, looking anxious. "Because I'm afraid it's only two bedrooms."

"Oh, no, no, no, sorry." The Doctor flapped a leather wallet that looked suspiciously like a fake badge at her. "Sorry. Official Scotland Yard business. Code name the Doctor. This is my partner, Red Riding Hood, and these are my associates from America, Agents Lumberjack and Sasquatch."

Dean grunted, and Sam felt his stomach sink. Maybe they shouldn't have let the Doctor do the talking. Why on earth would he use such ridiculous names?

But the landlady only smiled and said, "You must be friends of Sherlock's, then. I'm Mrs. Hudson."

"Mrs. Hudson, glad to meet you!" The Doctor shook her hand, grinning.

"I'm afraid Sherlock isn't here at the moment. He and John left for the day on a case, but they promised they'd be back—" She checked her watch. "Well, really, any minute now. Would you like to wait? I can put on some tea, and I have pie and biscuits in the oven."

"Oh, we wouldn't—" the Doctor started.

Dean cleared his throat and gave Mrs. Hudson his 'professional' smile. "Thanks, ma'am, that's very kind of you."

It was clearly the right thing to say—the woman's eyes lit up, and she pushed open the door, waving them into the flat.

They stepped into a living room that looked typical little-old-lady style—lace doilies on the side tables, flowery sofas, a hutch full of china on one wall. Sam couldn't help but smile. How many variations of this same theme had he seen over the years?

"Here, take a seat anywhere you like." Mrs. Hudson fluttered her hands vaguely at the couches. "Make yourselves comfortable. I'll be right out with the tea things."

"Oh, that's hardly necessary—" the Doctor started again.

"Thank you, Mrs. Hudson, we appreciate it," Dean said. He waited until she left the room, then made a face. "Do all little old ladies have to wear perfume that bops you one between the eyes?"

"We could've located Sherlock quickly without waiting for him," the Doctor said irritably.

"Pie, Doc. She offered us pie." Dean sat down, poking at one of the doilies on the table. "You never, ever pass up an offer of pie."

Amy laughed. "Is this one of your rules, Dean?"

"Right up there with driver picks the music."

Sam rolled his eyes and picked a seat on the flowery sofa. A tidy stack of daily newspapers sat on the side tables. Out of habit, he picked up the top one and started scanning the articles. He heard a faint buzz as the Doctor began messing with his sonic screwdriver again.

"So," Dean said in a low voice. "Can one of you explain how River—who's your daughter, right Amy?"

"Yeah."

"I'd still like to know how that worked. She's gotta be twenty years older than you."

"Don't let her hear you talk like that," the Doctor said absently. "She's slap you six ways to Sunday and have absolutely no qualms about doing it."

Sam couldn't help it—he let out a laugh and lowered the paper long enough to catch Dean's unamused look.

"Hey, Mrs. Hudson!" Dean said. "Where did you say Sherlock and John were?"

"They're are out on a case," Mrs. Hudson called from the kitchen. "They shouldn't be long. Sherlock said it was very easy, and he's generally a good judge."

China clattered. Sam turned the paper over. A small square of text below the fold and to the side caught his eye. Scotland Yard keeps mum on the sixth gruesome murder in two months…turn to page 5 for details…

A chill hit his spine. That many deaths, so quickly? He opened the newspaper and scanned until he found the rest of the article. Body discovered in underground parking garage…estimated time of death 2 a.m….security cameras blank…body appeared to be drained of blood…throat torn out…

"What're you reading?" Amy asked.

Sam jumped.

"Whoa, sorry." Amy leaned back, hands up. "Didn't mean to startle you, jumpy."

"Sorry, I just—" Sam rubbed his mouth, then folded the newspaper and pointed to the article. "Do you know about this?"

She read the article, then nodded, frowning. "The Invisible Man murders, yeah. Been reading about them for weeks. Why? What's wrong?"

Mrs. Hudson came from the kitchen, carrying a tray loaded with mugs of tea and plates of hot pie. Dean stood up and helped her start unloading the tray onto the coffee table.

"Amy," Sam said.

She looked back at him, eyebrows raised.

"Are all the murders the same? Throat torn out, blood gone, no evidence on security cameras?"

"What're you talking about?" Mrs. Hudson asked. "You sound like John and Sherlock. I—" she saw the newspaper in Sam's hand. "Oh, those awful, awful Invisible Man killings. Terrible things people do to each other nowadays. It's enough to give you nightmares. That's where John and Sherlock are off to, chasing down a lead on those killings."

Oh, crap. Sam looked over at the Doctor and Dean. The Doctor was busy staring down a couple of china dolls perched on the top of the cabinet by the door. Dean was just getting ready to shovel down his first bite of pie.

Sam cleared his throat. When Dean glared at him, he tilted his head and pointed at the newspaper article.

"Fine," Dean growled, grabbing the paper and looking over the article.

"Mrs. Hudson, did Sherlock say where he was going, exactly?" Sam asked.

"Well, no, he never does, but John left me an address just in case someone needed them—silly, really, I thought, what with cell phones and all, but you never can tell with those boys." She got up and started hunting through a stack of envelopes on another table. "John's always such a dear…ah, here it is." She held out an envelope with an address on it.

Dean shoved the bite of pie into his mouth and stood, talking around it. "Okay, sorry we have to run out on you like this, but we need to go. Doc!" He smacked the Doctor's shoulder.

The alien jumped, then sprang to his feet. "What?"

"We gotta go save your detective's butt, that's what." Dean nodded to Mrs. Hudson and shooed the Doctor and Amy out the door.

"Thanks, you've been a big help," Sam told Mrs. Hudson. He held up the newspaper Dean had dropped. "I don't suppose you'd mind…?"

"No, no, take it. And tell Sherlock he needs to pick up his own dry cleaning this time, the shop just called and it's been ready for two days."

"Uh, right. Yeah, I'll tell him." Sam hurried after the others.

As he pulled the door of 221 Baker Street closed behind him, he spotted Dean, Amy, and the Doctor waiting on the sidewalk. He hopped down the steps to them.

"So, the Invisible Man killer," Amy said. "What's with that? Don't tell me it's one of your things that go bump in the night."

Sam nodded, shoving his hands in his pockets and hunching his shoulders. "Unfortunately? Yeah."

"It sounds like vamps to me," Dean said. "Won't know for sure until we get to wherever they are."

Sam handed him the paper.

"Right." Dean passed it on to the Doctor.

"Vampires?" the Doctor muttered, reading the address. "We ran into some vampires once, didn't we, Amy?"

She nodded. "First time we took Rory anywhere. Romantic vacation in Venice, indeed." She looked up at the guys. "But those were aliens. I don't suppose there's any hope that these vampires could be aliens as well?"

Dean snorted and started across the street. "I dunno, sister. Are English vampires different than American ones? Either way, let's just hope they bleed like American ones, otherwise your brilliant detective could be up to his ears in a mess of crap."