John was preparing himself to saunter over to Sarah's desk and ask her to join him for dinner on a Sherlock and life threatening situation free date when his phone began to buzz in his pocket. He clocked the caller ID and answered with a hefty sigh.
"What?" Was all he managed to ask before a frazzled sounding voice cut across him.
"John! John, John, John. Something horrible is happening and you need to leave work and sort it out RIGHT NOW." John was vaguely reminded of his spoilt younger cousin who used to ruin every single one of his birthday parties by being a brat. Nevertheless, he felt his insides go cold.
"Sherlock, what is it? What's happening?" There was a tense pause on the other end of the phone line and John clutched the phone tightly to his ear, straining for a sound, well aware that Sarah, and everyone else in the clinic, was watching him like . . . like Mycroft. "Sherlock!"
"Oh God John!" A frantic whimper cut through the silence like a bullet, "It's coming to get me! Agh! NO! John, GET A CAB!" The line died and before he even knew what he was doing, John was making excuses to Sarah and darting out onto the street, hailing the first cab he saw.
221B was deadly silent when John climbed the stairs. He was resisting the urge to run – no ex-army doctor would dive into the unknown, even after their closest comrade. He stepped into the flat and was immediately accosted by a tangle of black hair and long, flailing limbs. A warm hand smothered his mouth and muffled his cry of shock and when he opened his eyes Sherlock's face was barely an inch away from his. John was aware of Sherlock's lack of understanding about personal space but this was ridiculous.
"You're here! Shh! You have to be quiet or it follows you about." Sherlock's eyes were as wide as saucepans and his grip on John's shoulder was much firmer than usual. Still, John didn't want to be played with.
"I swear Sherlock, if this is some kind of trick because you want tea or to use my phone I will have no qualms about phoning your brother and-" Sherlock glared at him, standing back from his flatmate and cautiously scanning the room as he moved.
"I know how to make tea John-" He stopped talking quickly as John's 'that's hardly the point and you know it isn't the point Sherlock' face made an appearance. "I locked it in the kitchen." He muttered instead, quite a contrast from the agitated Sherlock on the phone, John mused.
Shrugging his coat off, John frowned as Sherlock retreated into his room. Surely the world's only consulting detective wasn't scared of . . . well, what was it?
"Sherlock, what exactly is it in the kitchen?" There was no answer and John wasn't about to go and make himself look nervous over what was probably a mouse or a spider. If there was one thing John wasn't scared of, it was spiders. In Afghanistan there were camel spiders as big as your hand that used to chase your shadow or hide out in your boot and John had never been bitten. So, steadying himself slightly he opened the kitchen door and took a purposeful step inside.
When Mrs Hudson found them a few hours later, both huddled under Sherlock's bed sheet, quivering and whispering heatedly at each other, she thought she'd walked in on something quite different. Sherlock, however greeted her very enthusiastically and without a trace of shame, and they were both fully clothed.
"Turns out," She took great delight in telling Mrs Turner from next door, the next day, "That they're both scared stupid of butterflies! Grown men!"
"It's called lepidopterophobia." Sherlock supplied much to John's chagrin, as he stormed past them both and into a taxi.
John just hoped Anderson didn't hear about it.