John knew something was wrong as soon as he saw the envelope. To start off with, it had been forwarded from 221B Baker St. John hadn't lived at that address in months, and hadn't had anything forwarded from there in weeks. Secondly, it had no return address. Al that was on it was his name and his old address. The envelope was cheap, the kind used for greeting cards. Except whatever was in it was a lot thinner than a greeting card, as John could easily fold and bend it. John stopped what he was doing and smiled. He realized he was doing what Sherlock used to do, deducing things. "He could probably tell what's in this in three seconds flat," he thought. And just like that, the smile was gone, replaced by sadness.
It had been a while since he had thought of Sherlock. Though, of course, that was the point, wasn't it? You grieve, and then you move on, eventually forgetting everything altogether. His counselor would say that it was healthy for him to be thinking of Sherlock less. But every time he realized he was thinking of Sherlock less and less, he couldn't help but feel a slight twinge of guilt. He had tried explaining this to his fiancée, Mary, but she didn't understand. He felt he was moving on too fast, and no one, not even Mary, could convince him otherwise.
John was broken out of his mood by spilling hot coffee on his shoe. "Dammit," he muttered, walking to the kitchen to get a paper towel to clean up the mess. Then he remembered that he still had the mysterious envelope in his hand. It was probably just some old fan mail. There had been a lot of that after Sherlock's death. Some people wrote to express their condolences and support of Sherlock. Other wrote to express their commendation of Sherlock as a fake. Curious as to which one this would be, John opened the envelope. As soon as he saw what was inside, he dropped it and phoned Lestrade.