James Ballantyne is an agent with the British Foreign Office.
To be more accurate, the use of the term 'agent' would likely be frowned upon by the leadership at the Foreign & Commonwealth office (FCO), preferring more respectable terms such as delegate or representative. I use the term because Ballantyne will find a good deal of his time doing the sort of work that an intelligence operative would be comfortable doing, though in the case of Ballantyne it will be forced upon him.
Thanks to a very convenient review document on Ballantyne issued by the FCO, internal copy only for non distribution, we learn that Ballantyne has been employed by that department since June 2016, one month after he resigned his commission in the Royal Marines. "James Ballantyne came to the Foreign Office from the Marines; he had done two tours in Afghanistan and Iraq. At thirty-one, he knew progress in the services would be slow and he wanted to try something else."
The employment with the FCO would come despite an initial determination of "unsuitable" by the considering official, all stemming from a general court martial (GCM) he had to deal with. The charges had included manslaughter for "an unauthorized killing of three insurgents" for which he was acquitted and for insubordination which stuck though without penalty. Upon review by the man who would become his Section Leader at the FCO, the unfavorable rating would be overruled, stating he had "no doubt the assessment was wrong".
Prior to that bit of disagreement, Ballantyne had been a much valued member of the Service. Born in 1986 he saw his first serious action in Iraq when he was just 20 and then would continue to have considerable action over the next few years there and in Afghanistan. Outside his GCM, his reviews from his superiors were always top-notch.
Ballantyne was of interest to the FCO partially because of his expertise in languages. He speaks both Russian and Farsi as a native and is rated as 'adequate' in French and Arabic.