We go via Baker Street to pick John up, who looks rather annoyed, may I add, on our close timing. As we arrive at Scotland Yard, we get out and sprint up the steps of the building and straight up to Lestrade's main floor.

"Raoul de Santos is your killer," dad tells him as we find him, brandishing the file in his hand. "Kenny Prince's houseboy. Second autopsy shows it wasn't tetanus that poisoned Connie Prince - it was botulinum toxin. We've been here before," he continues, leaning closer to Lestrade as he tries to reach for the folder. "Carl Powers? Tut-tut. Our bomber's repeated himself." Lestrade begins to lead us into his office and we follow behind him.

"So how'd he do it?" Lestrade questions.

"Botox injection," I say in further realisation, remembering seeing the small pinpricks in her forehead.

"Correct," dad encourages.

"Botox?" Lestrade repeats.

"Botox is a diluted form of botulinum," I explain.

"Among other things," dad continues. "Raoul de Santos was employed to give Connie her regular facial injections. My contact at the Home Office gave me the complete records of Raoul's internet purchases. He's been bulk ordering Botox for months." I look over to John, smiling happily, but his stare at dad seems to be of anger. "Bided his time, then upped the strength to a fatal dose."

"You sure about this?" Lestrade challenges, and I look back over to him in disbelief.

"I'm sure."

"All right - my office," he says, continuing from where we left off. We begin to follow him, but John stops us.

"Hey, Sherlock. How long?"

"What?" dad frowns, both of us narrowing our brow in confusion.

"How long have you known?"

"Well, this one was quite simple, actually, and like I said, the bomber repeated himself. That was a mistake," dad explains, trying to step forward again, but John stops him.

"No, but Sherl... The hostage... the old woman. She's been there all this time."

"I knew I could save her," dad replies, staring at John intensely. "I also knew that the bomber had given us twelve hours. I solved the case quickly; that gave us time to get on with other things. Don't you see? We're one up on him!" At the beginning, we thought that maybe Mycroft was trying to distract us from this case, but according to dad, it seems to be the other way around. The bomber wants the missile plans.

"We need your computer," I tell Lestrade, who nods and allows dad to sit at the desk and open up the Science of Deduction. John and Lestrade move to stand either side of him, and I stand behind, peering over dad's shoulder. We watch with our hearts pounding as he types into the message box.

Raoul de Santos, the house-boy, botox.

The moment he clicks the send button, the pink phone rings, and I quickly slide my phone to mt ear as dad accepts the call.

"Hello?"

"Help me," the old woman says, anguished, and I can't help but feel some pity.

"Tell us where you are," dad says slowly, clearly. "Address."

"He was so ... " she begins, and I begin to panic. "His voice ..."

"No, no, no, no," dad says urgently, and I feel my hands getting clamy. "Tell me nothing about him. Nothing."

"He sounded so ... soft," the woman says finally, in an attempt to help us, but it's too late. I hear the single shot before the phone goes dead. She was so brave.

"Hello?" dad asks, but already realising the same as me. Lestrade looks across at me and sees my expression of complete horror.

"Sherlock?" he asks.

"What's happened?" John questions, but he ignores him.

"She's dead," I say softly. "He killed her." I lower my head in respect and Lestrade straightens up, sighing. John braces his hand on the back of dad's chair.

Note to Self: Details I have on killer

*Male

*Soft voice, probably Irish

*Potentially gay

*Excellent at IT

*Has a network able to plant cameras almost everywhere

*Is the spider in the centre of the web