Before taking a job in a spying organization, I recommend reading an entertaining 2003 novel I just finished,
Loose Lips by journalist, historian, and former intelligence community member Claire Berlinski. She wasn't the first to novelize their intelligence experience as an end-run against non-disclosure restrictions, but this is one I expect to remember the longest.
I find her subtitle -- "a roman à Claire" -- brilliant.
If not obvious: The subtitle is a takeoff on the phrase "roman à clef," meaning a novel closely following real people and events.