As it so often began, he got a phone call.
"Sherlock Holmes," he answered out of habit, already knowing it was Lestrade.
"Sherlock, there's been an accident."
Even from the slightest amount of tension in Lestrade's voice, Sherlock could tell this was serious.
"What?" he demanded.
"Don't panic, because he's fine, but John has been taken to hospital."
Sherlock was halfway down the stairs, shrugging his coat on by the time he finished that sentence.
"What happened?" he ordered, having already climbed in a cab and given directions.
"Some sort of explosion. We're still not entirely sure what happened, but John was conscious when the ambulance got there."
Sherlock frowned. "What was he doing there?"
"How should I know? I don't live with him." Lestrade sighed. "Sorry. I'll meet you at the hospital shortly, alright? Keep me updated."
Sherlock flipped his phone shut without replying.