Mary Watson` mouth is very close to Molly Hooper`s ear, which is perhaps necessary, due to all the screaming.

"Exits are blocked. I have the perimeter, and the dogs are go. You only have to give the word. The moment you see him bolt – "

Molly snorts like a Shetland pony as she is cutting tiny cubes of cheese and mushing them onto sticks with tiny cubes of pineapple.

"He`s not gonna bolt, Mary. He has promised to – mingle."

Mary steals a cube of pineapple and chucks it into her mouth. Her love of `Tea party Sherlock` holds no bounds and is matched only by her husband`s. John is currently videoing the event; partly as a charming childhood memory for Benedict to look back on, and partly because the lads at the Yard have chipped in a fiver each for a copy. He naturally, will not really be obliging them, but it was good to have something to hold over Sherlock for whenever he becomes too much of a git.

The red recording light is flashing as John homes in on Sherlock`s face while he stands, statue-like, holding a tea-pot and surrounded by at least six middle class London mummies. It could be carved out of alabaster.

"It is lovely to finally meet you, Sherlock. " An argyle-sweatered red-faced girl with a ginger pony-tail is giving him the benefit of her most flirtatious smile. Unfortunately, it is also her most toothsome and horsey smile.

"Me too," gushes a rangy and over-gilded blonde next to her. Both of them are fixing his face with a determined intensity. John homes in again. A third mummy adds to the throng:

"I simply could not believe, when I first met our little Molly, that you were Ben`s father. Sherlock Holmes, the Great Detective! I can`t get my husband off Dr Watson`s blog. He loves it. They all do at his club – a charming diversion for the busy man in the City."

`Statue Sherlock` suddenly comes to life, as if remembering a directive, and gives a (rather alarming) smile to the ensemble.

"Delighted I can be of service – tea?"

All six simultaneously hold out their china cups.

Mrs Hudson is carrying a large platter of chocolate Rice Krispie cakes from the overflow fridge in Molly`s 221A flat, and into Sherlock`s kitchen for some final sprinklings of icing sugar. She touches Molly on the arm and whispers, confidentially.

"How`s he doing, dear? I did make sure there was nothing – unusual – in the fridge, you know, just in case."

Molly puts the final cheese and pineapple stick into the cucumber crocodile (carved by Sherlock with his bowie knife) and smiles warmly at her landlady.

"Thank you so much, Mrs Hudson, but he has been so much better since Skylab was built. Haven`t seen a body part for months."

She carries in the reptilian masterpiece to a small and embarrassing round of applause from the mummies, which she decides, was a little unnecessary.

"Ah, Molly dear, what a charming little centrepiece! You have put your nurse training to some good use, I see." A smiling assassin of a mummy by the name of Alex was beaming at her with very expensive dentistry and a handful of pristine diamonds.

Molly had long since given up correcting them to the fact that she was a doctor, and actually did a little more intricate carving on a daily basis than a cucumber crocodile. Life was too short. She had her son`s special day to celebrate and her Consulting Detective to monitor.

"Thank you, Alex. I hope you`ll have a Krispie cake – Mrs Hudson has gone to some trouble right there…"

"Oh," Alex moves in, conspiratorially. "Your help? Is she quite alright? She seems a little – elderly – to be waiting on."

As John is filming this little exchange, Molly resists the urge to tell Alex to sod off, and smiles with gritted teeth.

"I couldn't possibly, darling," adds Miranda, the red-headed horse face. She is patting her stomach, primly. "Slave to the Atkins. Carbs are the enemy once one`s over thirty five." She smiles, glancing down at Molly`s abdomen.

"I`m thirty four," rejoins Molly Hooper, stuffing most of a Krispie cake, whole, into her mouth.

Back in the kitchen, Mary has found a bottle of white wine and hands her a glass.

"Just say the word," sotto voce, "and I`ll take them all out for you."

Little tears swim in Molly`s eyes.

"You say the sweetest things," she replies, patting Mary on the arm.

Benedict Sigerson Hamish Holmes is stomping proudly around the gathering on his two year old legs, holding a plush dinosaur. He isn`t used to large numbers congregating at his home (not ones without warrant cards and badges, anyway) and has his mother`s smiley and crowd pleasing persona. He also has his father`s beautiful eyes and raven curls, which contrast quite harshly to some of the pasty-faced and sparsely haired specimen`s attending as his special guests. The over gilded blonde, Olivia, is the proud owner of little Sheridan; a chubby and ruddy boy, with a mousey tufts and a permanently crusty nose to chin area. Excusable in a two year old, perhaps, but his peevish snatching and yelling are seldom addressed by his mother, who is too busy fluttering her assets vividly at Sherlock to notice her son`s juvenile misdemeanors.

"Mine!" Splutters Sheridan, reaching over to pull the dinosaur out of Ben`s hands.

Sheridan`s own hands are chocolate smeared (clearly not a slave to the Atkins) and Benedict looks, in horror, as is precious new toy is both sullied and stolen in the same instant.

"Noooo! He`s mine!" Ben uses his distinct height advantage to grab and lever the toy from the interloper, who, sensing when he is beaten, promptly sits down heavily on his nappy-padded backside and begins a fairly rigorous and insistent screaming.

"Mammmmmmmaaaaa! Mammmaaaaaa! MY dinosaur! It`s MINE!"

Mummies are rushing in from all directions to police the situation. Even `Mummy Olivia` tears her coy smile away from Sherlock long enough to rush to her son`s side. Scooping up the puce Sheridan, who now resembles a miniature post box, with his wide, rectangular screaming mouth, she turns on the birthday boy with enough disgust to wither a house plant at fifty paces.

"Sheri, my poor, poor little fellow … and you, Benedict Holmes, need to learn how to SHARE! All the lovely toys you`ve been given today, and you won`t let your little friend share your dinosaur? Poor manner, Benny – really poor."

Alex and Miranda ostensibly gather up their own pudding-esque offspring and begin extolling `the virtues of sharing` to a couple of bemused two year olds, who only want to play with Benedict`s toy garage and rub Krispie cake into the carpet – in that order.

A by-standing mummy shakes her head sadly and comments, in a stage whisper, about the dangers of bringing up a baby in `a Bohemian household`.

And, that about does it.

Molly places a restraining hand on Mary, as the latter is shifting forward into the fray. John stands on the other side of his wife, and simultaneously whispers in her ear:

"Wait – "

Sherlock Holmes has passed the tea pot to Mrs Hudson and is approaching the scene with all the aquiline grace and menace of a jungle cat.

" – he`s got this one."

The mummies raise their heads, alert to his presence, and the antelopes on the Serengeti have no idea what is coming to them.

Sherlock`s eyes are icy blue, but flashing a cold nitrogen fire that makes Alex shut her open mouth, abruptly.

He points to her, tilting his head slightly.

"You are worried that your husband is having an affair with your Au Pair. He is. You have checked your phone no less that eleven times since you arrived. The phone is not actually yours – since I don`t think `Hello Kitty` would be your choice of cover – but probably your employee`s, and you have stolen it, waiting for a text to arrive for her from your errant husband. Despite your age, you are wearing uncharacteristic glitter nail varnish and a large armful of bangles. That, combined with the clear botox injection marks in your forehead, tell me you are trying to compete with a twenty one year old girl who has caught your beleaguered husband`s wandering eye. By the way, it isn`t working."

Hardly drawing breath, Sherlock turns towards Miranda, of the horsey face.

"You have a secret online gambling habit – probably Bingo, despite it being `low brow`. You are a ruthless social climber, but clearly can`t quite abandon your roots. Your phone Apps show extreme interest in three sites, and you have recently lost your holiday money by gambling. Your nails are bitten to the quick with stress and your bag contains a bikini you are returning to the shop and a budget holiday brochure, in an attempt to salvage some kind of break for your unfortunate family. It seems unlikely."

As Sherlock turns to Olivia, Molly almost sees her shrink away, eyes wide and mouth open.

"Hmm – most interestingly, although you have extolled the virtues of sharing to my son, you only take your cocaine when your husband is away. When speaking earlier about local play parks, you mentioned an area by the name of `Anger`s Arches` which is a colloquial term for a local dealing spot and exclusively spoken by users and addicts alike. You have a permanent sniff which you blame on a cold, but also receding gums and a certain jittery agitation which cannot be ascribed to any type of virus I know. Perhaps the last hit is wearing off; children`s parties can be so trying, no?"

A strangulated sob escapes from Olivia, but apart from this, the room is completely silent. Even the tremulous Sheridan is mesmerised by Sherlock.

"Gosh," breezes Molly Hooper brightly, after around ten silent seconds have passed, "well if it isn`t just about time for the party bags!"

And John Watson lowers his camera; a very proud grin on his face.