Sleeper • Noun
A deep cover agent with a mission to penetrate the highest reaches of the target nation - long term project.

Spies • Noun
Professional liars

Slush fund • Noun
A fund raised by a group for corrupt practices, such as bribery or graft.

Surveillance • Noun
1. Careful observation of a person or group, especially one under suspicion.
2. The act of observing or the condition of being observed.