After ordering small espressos that cost twice as much as you's think they would, Sherlock starts in on his questions. When had Dinapoli arrived in London? Why had they waited until now to send out the sicari? Who had they hired, and who was organizing it?

The clerk, who John surmises is either a double agent, a triple agent, or working for Mycroft, is a useful source . He informs them that Dinapoli arrived in London about a week ago, the sicari had only been hired two days ago by a Sicilian employee, and it was Alrigo's crew.

At that news, Sherlock's eyes narrow. "Were they the ones responsible for that mess in Polynesia?"

"That's them."

Now John is feeling a bit out of the loop. "Polynesia?"

"You were in New Zealand at the time, having, as you put it, an adventure."

Ah.

Anyway, it appears that they've got their work cut out for them- this particular branch is known for it's ruthlessness, effectiveness ("only one person's ever escaped, and they committed suicide three minutes before they came through the door") and their leader's massive egotistical and megalomaniacal tendencies.

Apparently, the man has a pet hairless cat. That does not bode well for his mental stability.