EspionageThe act of spying, especially for a government.
Definitions:
The practice of spying or of using spies, typically by governments to obtain political and military information.
DefectorA person who leaves their own country in order to join another, usually in a situation of political crisis.
Definitions:
A person who has abandoned their country or cause in favor of an opposing one.
Double agentA person who spies on a foreign country while pretending to be a spy for it.
Definitions:
A person who pretends to spy for one organization or country while in fact spying for another.
InfiltrateTo covertly enter or gain access to.
Definitions:
Gain access to (an organization, place, etc.) surreptitiously and gradually, especially in order to acquire secret information.
ClandestineKept secret or done secretively, usually because illicit.
Definitions:
Kept secret or done secretively, especially because illicit.