Daniel Marchant is an agent with MI-6.
At the beginning of the first recorded adventure, he is a suspended agent and has been so for two months pending further investigation. His late father had been the head of MI-6 but was now in disgrace. The cousin Agency powers thought the elder Marchant untrustworthy and they engineered his removal. Though there was precious little against the son, the adage 'like father, like son' was on everyone's mind and Daniel Marchant did not help matters with his understandable protests.
Marchant is 29 years old as the series starts and has been an agent for several very busy, very dangerous years. He did not start out to be an agent when he became an adult. To anyone looking, he was on his way to an early grave through drinking and partying and letching and any other way a person can recklessly bring about his own end.
When Marchant was 8, his twin brother was killed in a car accident in Delhi where they all lived while his father was stationed there. Marchant took the loss particularly hard, understantably, but his mother did so even more. She eventually drank herself to death by the time the surviving brother was in his late teens and Marchant not only watched her do it, he seemed to feel that was the way to go.
The best schools educated him though he spent more of his time in bars and bedrooms than classrooms. Learning to be a journalist was for him very easy and that lack of challenge made the carousing even more common. By the time he neared his mid 20's, the likelihood of seeing the mid 30's was remote. That was when the offer to work for MI-6 and his father came and to the surprise of many, including perhaps himself, he took it. And with the new job and its challenges, a new lease was given him. He flourished and the next few years showed just how good he really was and he was enjoying life.
Then came his father's fall and his death and Marchant's own troubles. One thing his detractors should have studied, though, was that Marchant was a survivor.