Enzo walks downstairs the next day, finding Sherlock tidying up as John looks round the room "That's a skull." John says, motioning to the skull on the mantle with his cane, "Friend of mine. When I say 'friend'..." Sherlock responds. Enzo smiles lightly, going over to the sofa and sitting down. Sherlock gives him a look while tilting his head slightly, scanning him with his eyes. Enzo huffs slightly, rolling his eyes at his brother. Mrs Hudson walks in, picking up a cup and saucer as Sherlock takes off his coat and scarf "What do you think, then, Doctor Watson? There's another bedroom upstairs if you'll be needing three bedrooms." she tells John. "Of course we'll be needing three." John tells her. "Oh, don't worry; there's all sorts round here. Mrs Turner next door's got married once." Mrs Hudson tells him, whispering the last sentence. John looks at Sherlock who is oblivious to what is being insinuated, Enzo lying on the sofa with his knees to his chin. Mrs Hudson walks across to the kitchen and turns back to frowns at Sherlock and Enzo "Oh, Sherlock, Enzo. The mess you've made." She tells them, beginning to tidy up. "Oops." Enz mumbles sheepishly, running a hand through his hair.
John walks over to one of the two armchairs, plumping the cushion on the chair before dropping down into it. He looks across to Sherlock who is still tidying up a little "I looked you up on the internet last night." he tells him. "Anything interesting?" John asks. "Found your website, The Science of Deduction." John responds. "What did you think?" Sherlock asks happily. "You said you could identify a software designer by his tie and an airline pilot by his left thumb." John tells him. "Yes; and we can read your military career in your face and your leg." Enzo says. "And your brother's drinking habits in your mobile phone." Sherlock adds. "How?" John asks. Sherlock smiles and turns away as Mrs Hudson comes out of the kitchen reading a newspaper "What about these suicides then, Enzo, Sherlock? I thought that'd be right up your street. Three exactly the same." she tells them. Sherlock walks over to the window of the living room as a car pulls up outside "Four. There's been a fourth. And there's something different this time." Sherlock tells her. Enzo sits up as he hears the door open downstairs "A fourth?" Mrs Hudson asks him.
Lestrade walks up the stairs and into the living room "Where?" Sherlock asks. "Brixton, Lauriston Gardens." he responds. "What's new about this one? You wouldn't have come to get us if there wasn't something different." Enzo frowns. "You know how they never leave notes?" Lestrade asks. "Yeah." Sherlock responds. "This one did. Will you come?" Lestrade asks the brothers. "Who's on forensics?" Enzo asks. "It's Anderson." Lestrade responds. Sherlock grimaces "Anderson won't work with us." he tells the Detective. "Well, he won't be your assistant." Lestrade tells them. "We need an assistant." Enzo retorts. "Will you come?" Lestrade asks. "Not in a police car. We'll be right behind." Sherlock tells him. "Thank you." the Detective tells them, looking at John and Mrs Hudson before rushing off downstairs. As soon as the door shuts Sherlock leaps into the air, clenching his fist triumphantly as he spins "Brilliant! Yes! Ah, four serial suicides, and now a note! Oh, it's Christmas!" he smiles. Enzo smiles and gets up as Sherlock grabs his scarf and coat "Mrs Hudson, we'll be late. Might need some food." Sherlock tells their landlady. "I'm your landlady, dear, not your housekeeper." she reminds him. "Something cold will do. John, have a cup of tea, make yourself at home. Don't wait up!" Sherlock smiles, grabbing his leather pouch off the table as he and Enzo walk onto the landing. "Want to see if he wants to come with us?" Sherlock asks. "Of course he does." Enzo responds, shoving his hands in his pockets.
The brothers walk back to the living room, stopping in the doorway "You're a doctor. In fact you're an Army doctor." Sherlock says, making John look up from his paper. "Yes." John responds, getting to his feet and turning to the brothers. "Any good?" Enzo asks. "Very good." he responds. "Seen a lot of injuries, then; violent deaths." Sherlock remarks. "Mmm, yes." John nods. "Bit of trouble too, I bet." Sherlock tells him. "Of course, yes. Enough for a lifetime. Far too much." John tells them. "Wanna see some more?" Enzo smirks. "Oh God, yes." John responds. Sherlock and Enzo smile and head downstairs with John following "Sorry, Mrs Hudson, I'll skip the tea. Off out." John calls. "All three of you?" Mrs Hudson asks walking to the bottom of the stairs. "Impossible suicides? Four of them? There's no point sitting at home when there's finally something fun going on!" Sherlock smiles, grabbing her shoulders and kissing her cheek. "Look at you, all happy. It's not decent." Mrs Hudson smiles. "Who cares about decent? The game, Mrs Hudson, is on!" Sherlock smiles, walking out the flat. Enzo smiles and follows his brother onto the pavement "Taxi!" Sherlock calls. A taxi pulls up making the three of them climb in, Enzo sitting opposite his brother.
"Okay, you've got questions." Sherlock asks after a minute, putting his phone away. Enzo looks away from the window, pulling his jacket round him slightly "Yeah, where are we going?" John asks. "Crime scene. Next?" Sherlock tells him. "Who are you? What do you do?" John questions. "What do you think?" Enzo smiles. "I'd say private detectives..." John trails off. "But?" Sherlock asks. "...but the police don't go to private detectives." John finishes. "We're consulting detectives. Only ones in the world. I invented the job and Enzo joined me when he was eighteen." Sherlock responds. "What does that mean?" John asks. "It means when the police are out of their depth, which is always, they consult us." Sherlock tells him. "The police don't consult amateurs." John says. Sherlock and Enzo throw him a look "When we met you for the first time yesterday, I said, 'Afghanistan or Iraq?' You looked surprised." Sherlock says. "Yes, how did you know?" John asks.
"We didn't know, we saw. Your haircut, the way you hold yourself, says military. But your conversation as you entered the room said trained at Bart's, so Army doctor, obvious. Your face is tanned but no tan above the wrists. You've been abroad, but not sunbathing. Your limp's really bad when you walk but you don't ask for a chair when you stand, like you've forgotten about it, so it's at least partly psychosomatic. That says the original circumstances of the injury were traumatic. Wounded in action, then. Wounded in action, suntan, Afghanistan or Iraq." Enzo explains. "You said I had a therapist." John says. "You've got a psychosomatic limp, of course you've got a therapist. Then there's your brother." Sherlock tells him. "Hmm?" John hums. "Your phone. It's expensive, e-mail enabled, MP3 player, but you're looking for a flat share, you wouldn't waste money on this. It's a gift, then." Sherlock explains as John gives him the phone "Scratches. Not one, many over time. It's been in the same pocket as keys and coins. The man sitting next to me wouldn't treat his one luxury item like this, so it's had a previous owner. Next bit's easy. You know it already." Sherlock continues.
"The engraving." John responds. "Harry Watson: clearly a family member who's given you his old phone. Not your father; this is a young man's gadget. Could be a cousin, but you're a war hero who can't find a place to live. Unlikely you've got an extended family, certainly not one you're close to, so brother it is. Now, Clara. Who's Clara? Three kisses says it's a romantic attachment. The expense of the phone says wife, not girlfriend. She must have given it to him recently, this model's only six months old. Marriage in trouble then, six months on he's just given it away. If she'd left him, he'd have kept it. People do, sentiment. But no, he wanted rid of it. He left her. He gave the phone to you: that says he wants you to stay in touch. You're looking for cheap accommodation, but you're not going to your brother for help: that says you've got problems with him. Maybe you liked his wife; maybe you don't like his drinking." Sherlock continues. "How can you possibly know about the drinking?" John asks. "Shot in the dark. Good one, though. Power connection: tiny little scuff marks around the edge of it. Every night he goes to plug it in to charge but his hands are shaking. You never see those marks on a sober man's phone; never see a drunk's without them." Sherlock tells him, passing the phone back.
"There you go, you see, you were right." Enzo tells the doctor. "I was right? Right about what?" John asks. "The police don't consult amateurs." Sherlock tells him, looking out the window. "That... was amazing." John tells the brothers. "Do you think so?" Sherlock asks in surprise. "Of course it was. It was extraordinary; it was quite extraordinary." John nods. "That's not what people normally say." Enzo tells him. "What do people normally say?" John asks. "'Piss off'!" the brothers tell him simultaneously. Enzo goes back to looking out the window, putting his hands in his pockets as Sherlock keeps an eye on him. The cab soon arrives at Lauriston Gardens, making the three of them get out and walk towards the police tape strung across the road "Did we get anything wrong?" Sherlock asks John. "Harry and me don't get on, never have. Clara and Harry split up three months ago and they're getting a divorce; and Harry is a drinker." John responds. "Spot on, then. I didn't expect us to be right about everything." Sherlock says. "And Harry's short for Harriet." John tells them, making the brothers stop in their track "Harry's your sister." Sherlock realises. "Look, what exactly am I supposed to be doing here?" John asks. "Sister!" Sherlcok exclaims through grit teeth. "No, seriously, what am I doing here?" John asks. Sherlock starts walking again, making Enzo follow him "There's always something." he complains.
They approach the police tape where they are met by Sergeant Donovan "Hello, freaks." she greets the brothers, looking at Enzo's pale complexion. "We're here to see Detective Inspector Lestrade." Sherlock tells her. "Why?" Donovan asks. "We were invited." Sherlock responds. "Why?" Donovan repeats. "I think he wants us to take a look." Sherlock tells her. "Well, you know what I think, don't you?" she tells them. Sherlock lifts the tape and ducks underneath it, Enzo following "Always, Sally." he tells her. Enzo sniffs slightly "We even know you didn't make it home last night." he smirks. "I don't... Er, who's this?" Sally asks. "Colleague of ours, Doctor Watson." Sherlock tells her. "Doctor Watson, Sergeant Sally Donovan. Old friend." Enzo introduces. "A colleague? How do you get a colleague?! What, did they follow you home?" Sally asks, addressing John at the end. "Would it be better if I just waited and-" John starts. "No." Sherlock cuts him off, lifting the tape for John. John walks under the tape as Sally lifts her radio to her mouth "Freaks are here. Bringing them in." She says, leading the threee of them to the house.
As they reach the pavement, Anderson walks out in a coverall "Ah, Anderson. Here we are again." Sherlock remarks. Anderson looks at the brothers with distaste "It's a crime scene. I don't want it contaminated. Are we clear on that?" he asks. "Quite clear. And is your wife away for long?" Sherlock asks. "Oh, don't pretend you worked that out. Somebody told you that." Anderson tells him. "Your deodorant told us that." Enzo tells him. "My deodorant?" Anderson asks. "It's for men." Sherlock responds. "Well, of course it's for men! I'm wearing it!" Anderson exclaims. "So's Sergeant Donovan." Enzo tells him, sniffing slightly "Ooh, and I think it just vaporised." he smirks. "May we go in?" Sherlock asks. "Now look: whatever you're trying to imply-" Anderson starts. "I'm not implying anything. I'm sure Sally came round for a nice little chat, and just happened to stay over." Sherlock cuts him off, heading towards the door. "And I assume she scrubbed your floors, going by the state of her knees." Enzo adds, following his brother inside with John behind him.