You are the silence in between what I thought and what I said.

-Florence + The Machine, "No Light, No Light"

John was sipping coffee while Sherlock fiddled with the focus dials on a brand-new high-end microscope in the lab at Barts. He was trying to decide whether it was funny or cruel that Sherlock had scared away a student who had been using it by telling him his mother called and that it was about his father. He'd used such an ominous voice that John had nearly believed him, and the young trainee had run off with tears welling in his eyes. Perhaps it was both funny and cruel.

Now Sherlock was muttering quiet admirations at the microscope.

Mostly cruel, John decided, with a side of funny. Yes, definitely mostly cruel.

"Listen," John said, "the case… we're on a bit of a timetable, aren't we?"

"Hm? Oh! Yes." Sherlock hopped up off his chair and came round the table to grab the specimen he'd collected from the crime scene - soil - and started separating a small sample to put on a slide under the new microscope.

Behind him, John heard the door open, and he glanced up just in time to see Molly slipping in. For a half second, he didn't notice anything different about her, but just as soon as he'd turned back to his coffee, he looked up again and did a double-take.

Molly had cut her hair. Now she was sporting an angled sort of short haircut - longer in the front than in the back, and John had to admit it was cute. It framed her face. He grinned at her. "Looks nice, Molly."

"Oh - thanks," she said, smiling sweetly. She stopped at the edge of the lab table and looked at Sherlock expectantly. When he didn't even look up, she said hesitantly, "Um… Sherlock? The body of Mr. Edmundson… are you, um, done with it?"

At last, Sherlock looked up. "No," he started to say, "I still need to…" Then he trailed off, his eyes flickering over Molly's new look. His right eye twitched, and he took a breath to speak. "Your hair - "

Knowing what was to come, John cleared his throat. When that didn't get Sherlock's attention straightaway, he cleared it again, louder this time. That did get his attention, and the second Sherlock's eyes were on him, John dropped his chin and glared. Don't. Even. Think about it. He saw Sherlock's eyes widen very slightly - John, really! - and John's gaze hardened. Then, the detective seemed to put two and two together. His focus slid back to Molly.

"...Looks very nice, Molly."

Molly coloured deeply and averted her eyes, fidgeting with a button on her lab coat. "Oh - um - th-thanks. Thanks, Sherlock." She managed to make eye contact for a split second and smile brightly before all but running out of the room.

"Thank you," John said, after the door had closed behind her.

Sherlock only hummed and went back to his microscope.