The first time John Watson introduced his flatmate to his bride-to-be, Mary appeared in his bedroom wearing a black leather wristband, a confused expression on her face. “That wasn’t supposed to do that.”

“I’d say not,” John said dryly. “Usually you are much better about warning me when you are planning upon calling.”

Mary took the wristband off of her right wrist and handed it over to John. “Would you be a dear and put somewhere safe so that I don’t have to explain it to your Mr. Holmes when I meet him.”

John obligingly took the leather wristband from Mary’s outstreched arm and turned to open the box on his bedside table where he kept the drafts of his manuscripts. After removing few of the older manuscripts to make room, he shut the lid and turned back toward Mary, who had begun looking around the room in curiosity. “Now shall I put a kettle on, or do you want to finish inspecting my room before I introduce you to Holmes?”

“Watson have you seen my -” Holmes stopped speaking abruptly, eyes widening almost imperceptibly as he walked into the room and noticed Mary. “You weren’t here before.”

"I suppose that settles that." John stepped toward Mary, extending his hand for her to take. “Holmes, may I present Miss Mary Morstan, my …” here he trailed off, for he had rather meant to tell Holmes that he was engaged before introducing him to Mary.

“Your fiancée, yes, yes.” Holmes waved an impatient hand. “I was wondering when you would work out that I already knew. I was expecting her to be forgettable, like all of your other women.”

“John tells me you like to analyze people, figure out their secrets by looking at them.” Mary interrupted coolly, letting go of John's hand as she stepped toward Holmes. “Tell me Mr. Holmes, what can you tell me about myself? Or better yet, can you tell me how I appeared in John’s bedroom without walking past you in the sitting room first?”

Holmes looked at John with adoration. “My dear Watson, you’ve outdone yourself.” Holmes turned toward Mary. “The lack of dirt on your skirt and hands would indicate that you did not climb up from the street through the window, and similarly the lack of rope burns on your hands would suggest that you did not simply climb down from the roof either …” Holmes trailed off, staring at Mary’s feet for a long moment. “Gas balloon.”

“What about them?” Mary asked.

“The only logical solution is a small gas balloon which allowed you to get close enough to the window to jump in.” Holmes was missing his usual jubilant expression of a mystery well solved, clearly waiting for Mary to give him something more to go on.

Mary smirked. “Well if that is the case Mr. Holmes, you should go up to the roof to verify it - no gas balloon built by man can move fast enough to have left the line of sight yet.”

“Watson,” Holmes said, nearly knocking his microscope over as he quickly stood up.“I will return. Don’t touch the cactus in the sitting room and for God’s sake, don’t give me any hints!” Holmes tripped over Gladston in his haste to get to the staircase.

John and Mary looked at each other as silence fell in 221B. “So that was your Mr. Holmes,” Mary said. “He does seem quite exciting. I understand what you see in him John.”

“Thank you my dear,” John remarked dryly. “Although I don’t think he quite counts a mine, now does he?”

Mary smiled and held out her hand. “Come, let’s wait in the sitting room and speculate about the cactus until your Mr. Holmes returns from the roof.”