Sir Islands’ aide here is an original character, but his name continues the Holmesian naming trend (see “The Adventure of Wisteria Lodge” for the source). That, or it’s an homage to The Goon Show. Take your pick.

Aide: Sir Islands is not available right now. May I help you?

Walter: Yes, thank you, Mr. Eccles.

I need final confirmation on the “Capricorn” trip.

Aide: Mr. Dornez, are you aware that this is not a secure line?

Walter: All I need is a simple “yes.”

Aide: And what if it’s a “no”, and you need details on how to proceed?

Walter: Is it a no?

Aide: …It’s a yes.

Walter: Thank you for your help, Mr. Eccles.