This is the head of British intelligence in Vienna, Austria who teamed with The Outfit's Barnabas "Barney" Wolkowicz. Darby uses the services of a disgruntled Soviet employee to smuggle out a coding machine piece-by-piece over the course of three years. When it works, copies are installed in all Eastern capitals to capture volumes of raw text. Sufficient translators to keep up with the flow cannot be found. Darby is tall and thin, with a large hooked nose, domed forehead, and bold, expressive, yet guarded eyes. His full beard is ginger with gray mixed in. He had known the late Hubbard Christopher in Berlin. Darby pretends to have an affair with Barney's beautiful wife, Ilse, as the operation is brought to a close.