Sherlock stared at the DI. Greg wasn't up at this time of day, unless he got called to a crime scene, and he knew he hadn't been, since he'd made a habit since the consulting detective's return to tell him about all cases that came his way.
They had grown closer since Sherlock returned, especially when he'd admitted – because he wanted to, because he felt the DI had a right to know – that he'd been one of the three people Moriarty had threatened on the rooftop.
And ever since Greg had shown up at Baker Street to arrest Colonel Moran and seen that Sherlock was alive, Sherlock had called him by his first name.
Sherlock knew Greg, had known him for longer than he had John; he could recall every expression of the DI, his habits, his thought processes as familiar as Sherlock's own.
Something was wrong.
He didn't know how else to describe it. Greg didn't wear leather jackets, and he didn't stand on streets at dawn, looking as if he didn't have a care in the world. The mischievous twinkle in his eyes was normally far more subdued.
Plus, he had called Sherlock "Bill".
John was the only one, aside from Mycroft, who knew his full name. Sherlock had chosen to be called by his second name early in life. No one had ever called him "Bill". He wouldn't have put it past Greg to do so when he wanted to annoy him, but he didn't know. Unless John had told him.
He looked at the doctor, but John shook his head to indicate that he had no idea how Greg knew.
Sherlock looked at him once more and realized that he couldn't tell where the DI had been. In fact – he couldn't deduce him at all. It didn't make sense. Why couldn't Sherlock deduce him?
No. That wasn't right. He could deduce, of course, but what he got – spent a lot of time outdoors in the last few weeks, visited a pub last night, hasn't been to the Yard or St. Bart's in a while – didn't make any sense. He knew it to be false. Greg had spent yesterday at 221B, leaving around eleven pm, three hours before Sherlock and John had gone to the lab.
"Bill? You alright, mate?"
Greg looked at John, shaking his head disapprovingly.
"Where have you been dragging him?"
John blinked.
"Dragging?"
The DI's expression changed to one of concern.
"You guys okay? What have you been up to?"
Sherlock cleared his throat.
"We were working a case".
Greg rolled his eyes.
"I gathered as much. No other reason for you to run around."
"What are you doing here?" Sherlock inquired, because he couldn't stand not knowing any longer.
"The usual?" At Sherlock's confused look, Greg huffed impatiently. "I have been running around, trying to find the guy our genius here is looking for".
He waved his hand in John's direction. This answer only confused the consulting detective more. His flatmate answered before he had a chance to.
"Guy – I – Greg, we're not looking for anybody at the moment – "
The other man frowned. "What do you mean? Just two days ago, you demanded that I find him as soon as possible, and – " he stopped and his gaze wandered from John to Sherlock. "What are you wearing anyway? Are you undercover?"
"Undercover?" Sherlock demanded.
"Never seen John in anything different than a suit" the DI declared, and Sherlock knew definitely that something was wrong. The doctor rarely wore suits, preferring jeans and jumpers, and he was sure that Greg could count the number of times he'd seen him in one on one hand.
"Greg, I don't like wearing suits" John explained slowly. He shot Sherlock a look that clearly meant he expected his help and asked, "Why don't you come with us? I'll make you a cup of tea – "
"You? Make tea?" He laughed, but stopped when he saw John's face.
"Is he serious?" he asked. Sherlock needed a moment to realize that he was asking him – normally, this sort of question was directed towards John.
He nodded.
Greg cleared his throat.
"I – alright, then. How about we all get back to Baker Street?"
They agreed. Without giving each other any sign, they ended up on both sides of the DI. Sherlock's mind was racing. Greg hadn't been under more stress than usual lately, and he had never suffered from disorientation or hallucinations before. He had been fine when he had left their flat seven hours ago. Something must have happened in the meantime.
John didn't try to argue with him, and Sherlock decided that he should follow his doctor's example. He was about to call a cab when Greg suddenly took a turn, almost knocking him over, and walking along a side street.
During the next half hour they made their way to Baker Street through small alleyways, passing streets and corners that Sherlock wouldn't have thought the DI knew of. It wasn't the way he would ever have pictured Greg taking.
John glanced at him from time to time, to make sure that they were walking in the right direction. Sherlock couldn't blame him. He knew every street in London, but he wouldn't have pictured any of his friends to take this route.
And it wasn't just the path the DI had chosen – something about the way he moved was different as well. Close to the buildings, always in the shadows. The friend Sherlock knew liked to walk in the middle of the pavement, confident and with wide strides. This was how his homeless network moved – quickly, quietly, invisible.
Greg was walking fast, always a step or two in front of them, no matter how many times they tried to keep him between them, and eventually they allowed it. He wasn't running away at least.
Something was nagging at the back of Sherlock's mind, but he only realized what it was when they were nearly home.
Greg hadn't called Mycroft.
His brother and the DI had formed a sort of friendship while Sherlock had been gone – and even before that, Mycroft had had Greg check up on Sherlock, and he in turn had informed Mycroft of anything important. Now he believed Sherlock and his blogger had lost their minds – or were, at the very least, tired and confused – and he hadn't even tried to call him.
Sherlock contemplated trying again himself, but knew there would be no point. If something had happened to his brother's phone, the British Government would have sent him a text from one of the many others he had at his disposal.
It was better to deal with Greg first.
They followed him without saying a word, although Sherlock could feel John's glances. Naturally, the doctor was worrying about him worrying about Mycroft.
His flatmate would never cease to amaze him.
He realized they would be at Baker Street soon. They would get Greg in the flat first and then decide what to do.
"You're still not going to tell me what you were doing?" Greg asked, looking back at him.
"Business of Mycroft's" Sherlock replied courtly.
Unexpectedly, the DI laughed once more, leaving them to wonder what was so funny, Sherlock remembering that he and his brother had shared more than one glass of brandy before and after he'd returned and wonder why he would be amused by them taking one of the British Government's cases.
"I have to remember that one." Greg melodramatically wiped a few tears from his eyes. ""Business of Mycroft's", indeed".
Sherlock didn't know what to say. It had never been a feeling he'd particularly cherished, and now when his friend was clearly experiencing some kind of medical problem, it was more annoying than ever.
He looked at John and raised an eyebrow.
He shook his head, and Sherlock nodded. If John thought arguing wouldn't do any good, he wouldn't.
Although he really wished he could.
There was something about Greg – something about the way he talked – that, despite knowing about his confusion, made Sherlock uncomfortable.
He was too easygoing.
It wasn't that the DI didn't care; no, if he'd have stopped caring it would have been easier. But he thought that Sherlock and John were confused, and he took the fact remarkably well.
Too well for the man who'd shown up on his doorstep and looked through his belongings on danger nights more often than Sherlock could count.
He swallowed and continued to follow Greg.
Soon, they found themselves within twenty feet of the house.
Then something happened that Sherlock could never have predicted.
The door flew open, and Sherlock Holmes stormed out.
He was carrying a bag, wearing a jacket the consulting detective wouldn't have put on of his own free will, and talking into his mobile phone.
"I owe you. Thanks, Mike. I'll see you in half an hour."
He hung up and was about to walk into the other direction when Greg, who was staring at him like he'd just seen a ghost, called out, "Bill!"
He turned around and his mouth fell open.
This was going to be an interesting day, Sherlock decided.