"Good morning, my love", said John's voice as his hand was touching the back of Sherlock's neck. The microscope oculars, into which the detective had been staring all night, gave a small "squeak" sound as he removed his eyes from them. He turned around in his chair to face John and was immediately pulled into a kiss.

"I'm sorry", he said afterwards to avoid scolding. He knew he tasted like rubbish, his hair was in a mess and there were dark marks from the oculars around his eyes. But as always, John did not observe.

"Sorry? What for?" he asked, patting Sherlock's shoulder. "You didn't even disturb my sleep this night, although you have been working all the time, as I see."

He pointed at the stage of the microscope and the slide with the dried red stain on it.

"So nothing blew up this time?"

"No, unfortunately not", Sherlock replied, yawning. He decided not to tell John that he had actually slept through half the night, leaning onto the oculars, until the noises of John's showering had woken him up.

The experiment had failed either way. Distinguishing ketchup from tomato paste as an ingredient of noodle sauce had turned out to be extremely difficult. He would have to find a different way to prove that the victim had been murdered by her lover and not by her husband.

"Coffee?" John asked unnecessarily as he walked over to the coffee machine. In a back room of his mind, Sherlock tried to figure out why it was eight o'clock already, as his watch said, and John was still wearing his dressing gown, the one that made him look like a model in an advertisement for cheap deodorant. Sherlock was quite sure it was neither Saturday nor Sunday, rather just the beginning of the week, and John should have to go to work. But sometimes he lost track of time when he was working hard on a case, so he could be wrong.

"I won't go to work until midday because of my overtime", John explained while pouring two cups of coffee. With tired eyes Sherlock watched him stirring sugar into one of the cups and nothing into the other, which meant they had run out of milk again. Overtime? Yes, that made sense. It certainly sounded like something ordinary people had.

"So we can spend some time together", John went on, just as Sherlock's confused and exhausted mind began to muse about whether John's appearance in an advertisement would convince him to buy cheap deodorant. Probably not, but surely he would suddenly be spending a lot of time in front of the telly watching commercial breaks.

"Can I help you with the case?"

"No, you can't", Sherlock sighed, eagerly staring at the coffee mugs on the counter John was leaning against. "You've been out of it for too long because you were busy doing your boring job in the stupid …"

Without waiting for him to finish the sentence, John turned his back on Sherlock, opened a drawer and started rummaging around in it.

"Sherlock", he said after he had apparently found what he had been looking for. Coughing awkwardly, he came back to the experiment table and waved a white paper thing through the air.

"I have a present for you."

Sherlock's microscope strained eyes took a while to adjust, but even when he could finally see clearly, the paper thing did not seem to make any sense to him. A present? Presents were usually wrapped in colourful fancy paper and ridiculous bows. This was only an envelope.

"Why would you buy me a present? It's not my birthday", he said with an irritated frown. Had he missed something? Was today Christmas? No, he could not possibly have slept that long.

"I don't even know when your birthday is", John admitted. "You never told me. And because of that …" – he waved the paper thing again – "… you are getting this today. It's the third of March, the anniversary of the day we first met."

"Oh."

"Don't worry, I'm not expecting you to have bought anything for me."

That would have been the least of Sherlock's concerns, but he nodded anyway.

"And it's not from me only", John continued. "We all thought you deserved a little thank-you gift after all the efforts you took to arrest the serial killer last month. I mean, you even tried to be polite to the witnesses!" He laughed. "So Mrs Hudson, Lestrade, some of the cops, Mike Stamford, Molly and I decided to get this for you because we thought you might like it."

Fighting his way through the fogs of the early morning that were clouding up his mind palace, Sherlock tried his luck at a deduction. A present people thought he might like. Many people involved – that meant John could not afford it alone. That meant it was expensive. Very expensive, but very small. Could be jewellery.

"Is this a …?"

He shook his head and quickly discarded the thought before the words could slip out. Wedding rings were never put into envelopes. Before he could make a complete fool out of himself with wrong deductions John would tease him endlessly about, he snatched the envelope out of his hand. It contained nothing but another small piece of paper. The address of a restaurant in Knightsbridge was written on it in ornate letters.

"Dinner?"

"Yes, that's the name of the restaurant. Molecular kitchen. It has to do with chemistry!"

John smiled. Sherlock had no understanding of his obvious enthusiasm.

"We go out for dinner almost every day, John", he stated. "Unless you cook."

John's smile grew wider.

"Exactly! I'm tired of being the one who always has to cook. It's time for you to learn some kitchen skills. You would only be bored by an ordinary cooking course, I thought, but not if there is some complicated organic chemistry involved. The Dinner's chef, Mr Vallefiori, gives courses in molecular cooking. They cost a fortune, but I heard they're worth it. He prefers to call it 'experimental cuisine' – now don't tell me that doesn't sound like something you do by accident every day anyhow." He tapped the piece of paper. "This is the voucher. You are registered."

"But I can cook", Sherlock complained. "I made dinner for us on New Year's Day, for example. When you were too hungover to get up from the sofa."

"Oh, that." John shuddered at the memory. "That stuff. It looked like marmalade, tasted like fish and smelled like rotten eggs. It made the whole flat stink. Which is especially helpful when you have a hangover, I can tell you. And that was sarcasm, in case you didn't realise."

"Of course I did", Sherlock snapped. "And the smell was not from the food. It came from the hydrogen sulphide experiment I had running on the other hob."

"Well, the only good thing about it was that my jacket still smelled of it the next morning and I had a lot of space on the tube."

Sherlock read the text on the voucher again and frowned.

"Wednesday the fourth? But that is this week, isn't it?"

"Tomorrow, yes. It starts at 11 am." John fetched the coffee mugs from the counter, pulled up another chair and sat down next to Sherlock. "It could be useful, you know? We've already had more than one case involving food ingredients and kitchen equipment, and it was a problem for you every time because you didn't know enough about it. Reading books is not always sufficient. Some things require practical experience."

Rubbing his eyes, Sherlock accepted the cup of coffee John was holding out to him and drank a sip of it. The bittersweet taste and anticipation of a high dose of caffeine made the day immediately better.

"I don't have the time. I'm working on a case", he said brusquely. This would put an end to the discussion. That being settled, he began to look forward to finishing his coffee and then going back to work.

That was before he saw John's reaction. His flatmate's shoulders slumped, his eyelids dropped slightly and the corners of his mouth pointed downwards. Disappointment. Not good. Disappointment could result in unnecessary arguments that would cost a lot of Sherlock's precious time.

It might also have even worse consequences. The arguments could get out of hand and destroy their relationship. Horrible visions ghosted over Sherlock's mental screen. John would stop praising him, would not want to work with him anymore and refuse to sleep in Sherlock's bed. He might even start dating girlfriends again. Sarah, Jeanette and the one with the nose … What if they came back?

On a caffeine-induced quickstart, Sherlock's mind started racing to find a solution to this problem. How could he make the corners of John's mouth point upwards again and still prove to Lestrade that the police was wrong about the murderer?

Within seconds, he developed an idea and congratulated himself on it being one of the best he had ever had.

"Wait, the case is indeed not that interesting", he proclaimed. That was a blatant lie. In fact, it was one of the most challenging ones he had come across in more than a month. But now, weaved into the new plans he had just developed, it would become even better.

"I've almost solved it anyway, there's just a tiny detail missing", he declared excitedly, jumping up from his chair and nearly spilling his coffee.

"Perhaps I can produce it until tomorrow at 11 am and provide Lestrade with the evidence he needs. If not, I might as well take a day off, as you suggested so many times, and get somebody else to solve it for me."

"Somebody else?" John asked in a sceptical tone. Sherlock gave him a sly smirk.

"You'll see."