Hugh Donovan is an agent with the British King's Foreign Service.
By the strictest interpretation of the job description, Donovan would be considered a courier in the employ of the British Crown. The history of this job goes back to the 12th Century. From the time the Foreign Office was created, around 1780, those working this job would be under its control though apparently in 1824 management was handed to the Home Office and a special group called the Foreign Service Messengers Department.
When at home, which we are told is sadly infrequent, Donovan enjoys lounging in his "old brown velveteen coat, much rubbed at the elbows", smoking his interesting "exquisite" Russian cigarettes. He is described as a "gay, devil-may-care cosmopolitan who knew the world from Dover to Delhi, or from Hammerfest to Hammersmith, better than any living man". In those apartment rooms, he has the services of a valet named Bettinson, a devoted and friendly man who looked "more like a race-course tout than a gentleman's servant". Bettinson is very much in on the work that Donovan does and is called upon now and then to lend a simple hand.
By the time we first meet him, he has been an operative for quite some time and was very much in the know about the inner workings of not only the intelligence communities of Europe but also the nature of his employers. "As an official of the correct-dealing, but much-maligned Foreign Office, he was able to discriminate between the truth of the progress of our arms and the picturesque fictions as given to the Press in accordance with the War Office and Admiralty instructions". That statement is particularly telling in two parts, the first being that the Foreign Office might be badly talked about but was invariably "correct-dealing", and the second being that intel given to the Press by the military was routinely both colorful and inaccurate.
Giving him persistent reason for concluding his important missions all over Europe and northern Africa is his relationship with his lover and friend, the lovely Mabel Metcalfe, daughter of a former British ambassador to Berlin. While he is not able to confide in her the exact nature of his all-too-frequent missions, she does know that he is an agent and that his work is extremely dangerous and important.
Donovan is much fond of disguises, simple changes in wardrobe and posture and demeanor allowing him to blend into the most common of places as a beggar or a tradesman. He is also well disposed in methods of forgery to provide himself with foreign identities as needed, each looking completely authentic. Speaking many languages with ease as a native, Donovan is capable of passing himself off as many different nationalities. Speaking one foreign language with the dialect of another foreign language, such as talking German as though by a Dutchman, is impressive, indeed.
Said by Donovan when concocting a crazy plan, "The game is certainly worth the candle."