Sherlock Holmes dug into his pocket to pay the cabbie, but his hand came out empty. Holmes looked at Watson, who shrugged nonchalantly.

"I thought we agreed that I would pay the cabbie on the way there, and you would pay him on the way back, Holmes."

The said cabbie chose that moment to cough quite loudly.

"Watson," Holmes replied, "We need to pay the cabbie. You are the only one with money at present. Therefore, you must pay him."

"Fine," he said, digging around in his pocket, "but you will pay me back, right?"

Holmes decided not to answer.