(A/N: This is my first Sherlock fic, so I would love to know whether you think it's in character or not. Also, if you figure out the "mystery," please don't spoil it for others! And as much as I love and adore slash, this fic is probably not going to have any. Thanks for reading!)

Lestrade burst through the door of 221B Baker Street, his face flushed.

"There's been a bomb. At Victoria Station."

Sherlock looked up from the newspaper he had been examining.

"You wouldn't be here if was an ordinary bombing. What's unique about it?"

"I've just been talking to one of the witnesses – she says she saw a man in a long black coat drop a package on the platform, but he got on the train before she could see his face. It looked plain – just wrapped in brown paper – but the next thing she knew, well, you can imagine."

"I don't imagine. I observe. Can you take me to her?"

"Of course. We've got her down at the station. Will you be taking a cab?"

"Yes. I'll pick up John on the way, he's with Sarah again. Can't imagine why."

"All right then. See you there." Lestrade hurried out. Sherlock followed a minute later, wrapping his own long, black coat around himself.

"Close your eyes. Let the memory overtake you. First, think of the man. Exactly how much did you see of him? Hair, height, shoes, hands? I need every detail you can give me."

The woman Sherlock was interrogating was in her early 30s. She had strawberry blonde hair pulled back in a ponytail and wore a black business suit. She was still visibly shaken from the incident as she quaveringly answered.

"He was…not quite as tall as you. And he had very short blonde hair. A military cut, possibly." Sherlock glanced fleetingly at John, then back to the woman.

"Anything else? His shoes, his gait, did he limp? I need data!"

"I…I think he was wearing black boots. But it was all so fast, I don't know for sure!" Her eyes started to tear up, and she wrung her hands. Sherlock started to pace, and John took over talking to the woman.

"It's alright, you're safe now. What about the package? Did anything stand out about it?" She swallowed, composed herself, then began to speak again.

"It had a string wrapped around it. It looked rather hastily done, like he hadn't put much effort into it. But that's all I can remember, and then it exploded, and…" She broke off again, noisily crying. Sherlock rounded on her again, but John put up a hand to stop him.

"Show a little courtesy!" he hissed. Sherlock only stared at him, then moved John's hand out of his way.

"Are you absolutely sure that you've told us every detail you can remember?" he started. She glanced up at him, teary-eyed, and nodded.

"I think we're done here, I'll make sure you can get into Victoria to look around," interjected Lestrade.

"Yes, that sounds like a lovely idea," said John, grabbing Sherlock's arm and forcefully steering him out of the room.

The three men pieced their way through the wreckage at the station. Workers from the bomb squad were scattered around, looking for fragments of the responsible weapon. Sherlock was muttering to himself about brown paper when Lestrade's phone went off. After a curt conversation, he hung up, and with a grim face, relayed what he had heard.

"There's been another one. At the girls' school up the road." Without another word, they ran to the street, caught a cab, and were soon on their way to the scene of the next crime.

A gaping hole in the school's playground greeted them. Many of the girls, who were being held back by their teachers, had ash on the white dresses that comprised their uniforms. Breaking free from John, Sherlock rushed over to the students.

"Did you see anything, did any of you see anything?" he said loudly. One girl of about nine stepped forward; her blue sash was nearly falling off.

"I saw a man walking outside the fence. He threw something over the fence, ran away, and then it exploded! I want my mummy!" She latched onto the tail of Sherlock's coat and began sobbing into it. He looked utterly baffled.

"Your mother won't be of any use, the damage has been done already. You don't appear to be injured. Now tell me, what did the man look like?" She backed away, and looked him up and down.

"Well, he had a coat that looked awful like yours. But his hair was the opposite of yours."

"You can't have opposites in hairstyles, there are far too many variables. What exactly did his hair look like?" One of the teachers had stepped toward the girl, and was holding her hand. She seemed to gain some courage from this, and answered:

"It was…yellow, I guess. And short like your friend over there." She gestured to John, who exchanged a significant look with Sherlock.

"Indeed. Can you remember anything else about him?" he said brusquely. She thought for a moment, and then could only offer "He looked mean. Like the boy on my street who always knocks me off my bicycle."

"Indeed. Well, that's all I need from you. John!" he called out. "I need your phone."

Looking somewhat annoyed, but not surprised, John pulled it out of his coat pocket and handed it to Sherlock as the three men drew some distance away from the others.

"If the first bombing was at 11:00, and this one was at 12:00, we may have a serial bomber on our hands. According to the phone, it is precisely 12:52 P.M. right now, which means we should have new evidence shortly."

"New evidence?" sputtered Lestrade. "D'you mean he's going to strike again?"

"We shall see," said Sherlock, "And if we acquire more data, it will be easier to pick out a pattern in order to preempt him. It is now 12:53 – oh, what's this, a text? How would he…" Sherlock peered closely at the message on the screen. " 'To my kitten – when will you be back?' Is it a clue, a code, a-"

"It's for me, thanks," said John, hastily grabbing the phone away from Sherlock. "From Sarah, if you must know."

"Kitten?" Sherlock exclaimed, grinning. "You actually let her call you that?"

"This wouldn't have come up if you would actually carry your own phone around with you," said John grumpily. They waited in silence for the next few minutes, with Sherlock doing his best to smother his giggles. Finally, Lestrade's phone rang, and he quickly answered it.

"Another bomb? Where?" Sherlock and John stared at him, rapt. "It's a department store, right in the heart of town."

And at this, they were off.

The road was thick with people hurrying back to work after their lunch hours. Even a small bombing could not do much to alter the flow of human traffic in central London. Sherlock, John, and Lestrade picked their way through the crowd toward the smoking hole of a storefront. The shop's display products were scattered piecemeal on the ground; a pair of mittens here, a kettle there. The customers had been herded to one side by several police officers, with whom Lestrade exchanged curt greetings. After a brief conversation, he returned to John and Sherlock.

"It's our same guy. You better see a pattern soon, because I want this to end," he said firmly.