As the door closed behind them his guide pressed a lighter into his hand and pointed to the far corner of the unused warehouse.
"You'll find a couple of candles over there."
"Don't tell me that something as simple as lighting candles is beyond the man who broke me out of captivity." Sherlock said snarkily.
His companion turned to face him.
"I could do it," he said mildly, "but you're the one who needs the light. I can work just as well without." And he turned away and walked towards some upturned crates.
"Work?" Sherlock felt suddenly wrong-footed.
"You're a scientist Mr Holmes; you know the likelihood of infection if we don't clean up those scrapes you picked up in the catacombes." He started unpacking the backpack, his hands swiftly identifying each item he retrieved from its depths. "What, lost for words?"
"How do you know me? Who are you?" Sherlock lit the candles, their yellow light making little difference in the gloom.
"You're the man Moriarty believed was his intellectual equal." The other man worked as he spoke, cleaning and dressing Sherlock's wounds. "He believed you could help him develop mind-bending drugs to use against the government."
"But who are you?" Sherlock asked again
"My name is John, and I'm the only person standing between you and gang leader Barrymore."