Ascension

British spy Elliot Kane is forced out of semi-retirement to investigate a colleague's suspicious death on Ascension Island, a remote and rocky outpost of the British military in the middle of the Atlantic. Despite foiling a plot to incite a new world war, Elliot Kane has been on probation with MI6 since his rogue misadventures in Kazakhstan. Granted a job teaching literature to college students, he surprisingly enjoys a conventional life away from the intelligence services.
Then a former colleague reaches out with a request: one of her tech specialists on a long-term, covert mission has killed himself, and the agency needs to find out why before proceeding with the vital operation. The carrot in this offer is helping his old friend; the stick is more disciplinary action if he doesn't comply. So Kane takes on deep cover again and heads to one of the most remote places on the planet, Ascension Island.
A curious legacy of England's imperial past, Ascension is a desolate rock made of dead volcanic cones located in the Atlantic Ocean halfway between Brazil and Angola. Only employees and their families are allowed to reside there, and the island contains both British and American military bases. After learning that a teenage girl disappeared on the same night as the technician's suicide, Kane finds himself with two mysteries to solve.
With local tensions running high, he needs to move quickly before suspicion falls on him. Kane soon realizes the island has more secrets than even the government knows, some leading straight to the highest offices in London.