At the door stands a middle aged man wearing a grey suit and carrying a briefcase, and who smiles politely when Sherlock opens the door.

"Mr. Holmes," he greets. It's not a question. "My name is Harry Wilson, I'm a lawyer. My former company used to represent Rupert Mannion, and I have some information you might be interested in."

His accent is American, and he's recently arrived in the country. He also seems very pleased to be there, beyond mere politeness.