The fire crackled in the grate a few feet away, a pot of Earl Grey and a fruit scone sat by his elbow, and if he cared to shift his gaze away from the afternoon edition of The Times, Mycroft knew he might be mildly charmed by the unseasonal sprinkling of snow drifting past the window. It was something of an indulgence to be here so early in the day, but he had been forced to spend the previous two hours being obsequious to some minor members of the Bahraini royal family, so it was also well-deserved.

He was just starting to think about pouring some tea, satisfied that it would now have reached its optimum temperature, when one of the club's waiting staff approached with a folded note on a tray. Before he had even opened it, Mycroft could feel that this was going to signal the end of his peace and solitude.

His instinct was entirely correct. He read the words on the paper, then refolded it until it was small enough to shove up someone's nostril – which, depending on what happened in the next few minutes, might actually have some relevance.

Rising from his chair, he gestured for the young steward to bring his tea and scone, and go with him – a gesture that the steward promptly mistook for Mycroft wanting the items returned to the kitchen, resulting in a brief but ridiculous pantomime of charades between the two of them. Most of the time, there was a lot to be said for the old Diogenes Club statute of complete silence, but on occasion it was extremely impractical.

As he was leaving the room, he felt his phone vibrate in his jacket pocket. A communiqué from Anthea.

He insisted it was important. Sorry.

Mycroft rolled his eyes. Confirmation of precisely what he suspected; his brother had only been back from the dead for five minutes, and already he was finding his previous form. (The nostril-sized piece of paper was starting to seem more relevant by the second.)

"This way, sir," said the steward, once they were in the more lenient surroundings of the Stranger's Room.

The direction was hardly necessary; it would have been extremely hard to miss the six-foot man in an overcoat and scarf pacing restlessly between the chairs. The steward set the tea tray down on one of the low tables, and Sherlock immediately swooped in and grabbed half of the buttered scone.

"Thanks," he said, around a mouthful of crumbs. "Plans for dinner fell through."

"To what do I owe the pleasure?" Mycroft asked, arranging himself in the more comfortable of the two chairs. "It's been, what, a whole three hours since we last saw each other?"

Sherlock dropped into the other chair, leaning forward to take the other half of the scone while still chewing the first.

"So, have you come to tell me you've caught the terrorists?" Mycroft continued. "Or was it just too lonely at Baker Street?"

"No," Sherlock replied, frowning. "And do you know who else isn't lonely? The hat man. I returned his property to him this afternoon."

"Oh yes – the 'hat man'," Mycroft replied with a smile, folding his hands in his lap. "So how did we do?"

"Our deductions?" Sherlock said, sounding a little distracted. "Like I said, he isn't lonely. Girlfriend, apparently."

"Mm. Well, no accounting for taste, I suppose."

Mycroft leant forward and poured some tea into his cup (almost certainly stewed by this time). He was still leaning over the table, pouring in the milk, when Sherlock spoke.

"Why didn't you tell me that Molly Hooper was engaged?"

Mycroft sat back slowly, watching his brother the whole time. He immediately began to suspect that everything Sherlock had said previously was just a preamble, his version of small-talk.

"I wasn't aware," he replied. He got the distinct impression that asking Sherlock to pass on his congratulations wouldn't go down particularly well.

"'Wasn't aware'?" Sherlock parroted, screwing up his face in disgust. "How could you not be aware? I left you with very clear instructions for the time I was away, Mycroft."

"Yeess," Mycroft replied slowly, settling his cup of tea in his lap. "'Safe, protected, above suspicion' – those, I believe, were your instructions, Sherlock, and they were carried out to the letter. I didn't fully appreciate that you also expected me to intervene in Dr Hooper's…romantic pursuits."

Even speaking those words out loud made Mycroft feel as though he'd dropped several IQ points.

"But how could you not know?" Sherlock insisted. "You would have had surveillance."

"Yes, and the team involved would have observed and carried out checks on any individual paying regular visits to her home," Mycroft said, taking a sip of tea (it was stewed - damn). "I can only assume that the gentleman in question – Dr Hooper's beau – must have passed the checks; therefore, there would have been no reason for me to get involved."

He watched his brother, whose long fingers were working away, agitatedly, at a loose thread on the arm of his chair.

"But if I had known," Mycroft continued, as their eyes met. "Why would it have been significant?"

"It wouldn't," Sherlock snapped back.

Another scone had appeared on the table (apparently, one could get the staff), and Mycroft set down his cup and picked up the plate so he could start buttering his scone.

"I see," he said. "So you haven't come here to ask me to make the nasty man go away?"

"Don't be ridiculous, Mycroft," his brother retorted.

There was silence for a while, but it wasn't a peaceable one; out of the corner of Mycroft's eye, while he was trying to enjoy the rather excellent scone, he could see Sherlock's knee bouncing with nervous energy, his fingertips drumming on the armrest.

"I…I actually didn't go alone to see the hat man," Sherlock said eventually, suddenly switching to a tone of casual insouciance.

"Oh? Has Dr Watson overcome his violent loathing for you already?"

"No," Sherlock replied, pursing his lips. "I took Molly with me. For the whole day actually; several investigations. I find I work better if I have a sounding-board."

It had been a while since Mycroft had felt his eyebrow rise so quickly.

"Ah yes," he said, working a strawberry seed out from between his teeth. "That would explain the aftershave that you weren't wearing when I saw you earlier today. Vitally important to smell alluring for one's 'sounding-board'."

"Shut up, Mycroft," Sherlock growled. "It was actually a very satisfactory series of cases; just what I needed to get back in to the swing of things. And Molly acquitted herself very well – she has a useful set of skills that complement my own. Although, obviously, just a one-off."

"Oh?" Mycroft said. "Is there a reason it couldn't continue? It's a professional arrangement, after all, one friend helping out another."

He heard Sherlock clear his throat, his eyes fixed on his knees.

"I'm led to believe that 'the fiancé' might not like it," he replied, in a clipped tone.

"The jealous sort, is he?" Mycroft asked. He was starting to find this conversation tiresome in the extreme; he'd almost prefer the Bahraini royalty and their shopping list of armaments.

"I've no idea," Sherlock replied, waspishly, as though it had been a stupid question. "I know virtually nothing about the man. But isn't that what people are like? Get absurdly possessive over the people they're attached to?"

Mycroft's eyebrows rose again.

"Yes," he said, languidly. "I can see how that might be possible."

Sherlock didn't react at first, but then his eyes shot up, narrowing in annoyance as he cottoned on to the underlying satire of Mycroft's words. Mycroft smiled pleasantly in return, which had always had the effect of vexing Sherlock further – and in this case, his brother knew that to react in anger would be to protest too much.

"Anyway, it was a productive day's work," Sherlock said eventually, springing out of the chair and almost blurting his words. "Some promising leads to follow up, from the hat man, as a matter of fact – CCTV footage from the Underground, District Line, think it might mean something."

"I do hope so," Mycroft replied, mildly. "I would hate for your day to have been wasted."

Sherlock refastened his scarf and retrieved his leather gloves from his coat pockets, looking intently at the oak panelled wall as he did so. Mycroft saw his gaze drift to the floor, then flick sideways in his direction.

"Don't suppose you fancy some chips?"

Mycroft frowned - not exactly what he'd been expecting to hear.

"Sadly, I must decline, delightful though that sounds," he told Sherlock. Mycroft couldn't be sure when he last ate chips of the variety that Sherlock was no doubt proposing; he didn't suppose the pommes allumettes on the club's 'casual dining' menu bore much resemblance. He also suspected that he wasn't Sherlock's first-choice dining companion.

"The world didn't stand still for the past two years, Sherlock," he said, watching his brother pull on his gloves. "Is that a shock to you? Your faithful hound has a new master, and your mortuary companion has found someone in the land of the living. I tried to tell you – people move on, it's what they do. Don't get involved."

"Says the man who bought a suit of armour from an auction house just so he would have someone to talk to," Sherlock shot back. "Thanks for the scone, bruv."

He started to walk away.

"Oh, by the way," Mycroft called. "I believe you can expect our parents to descend at some point soon."

Sherlock stopped and turned slightly.

"Why?" he asked, with a vexed expression.

Mycroft sighed, crossing one leg over the other.

"Apparently, they've been 'worried' about you, or some such thing," he said.

Sherlock pulled another face.

"Tell them I've got some terrorists to catch," he replied.

Mycroft didn't think that would act as a much of a deterrent to their mother, but as he watched Sherlock flip up the collar of his coat and stride towards the lobby, he felt oddly relieved – if it wasn't for the distraction of terrorist plots, and if it wasn't for conveniently-positioned fiancés, his brother might have come dangerously close to doing something very stupid.