Sleeper agent

A sleeper agent is a spy who is placed in a target country or organization not to undertake an immediate mission but to act as a potential asset if activated. Even if unactivated, the "sleeper agent" is still an asset and is still playing an active role in sedition, treason or espionage by virtue of agreeing to act if activated. Sleeper agents are popular plot devices in fiction, particularly in espionage fiction and science fiction. This common use in fiction is directly related to and results from repeated instances of real-life "sleeper agents" participating in spying, espionage, sedition, treason and assassinations.

There are different types of sleeper agents, most being misportrayed in movies and in books. In espionage, a sleeper agent is one who has infiltrated into the target country and has "gone to sleep", sometimes for many years. The agent does nothing to communicate with the sponsor or any existing agents or to obtain information beyond what is in public sources. The agent can also be referred to as a 'deep cover' agent. The agent acquires jobs and identities, ideally ones that will prove useful in the future, and attempts to blend into everyday life as a normal citizen. Counter-espionage agencies in the target country cannot, in practice, closely watch all those who might possibly have been recruited some time before.

In a sense, the best sleeper agents are those who do not need to be paid by the sponsor, as they are able to earn enough money to finance themselves. That avoids any possibly traceable payments from abroad. In such cases, it is possible that the sleeper agent might be successful enough to become what is sometimes termed an "agent of influence".

Sleeper agents who have been discovered have often been natives of the target country who moved elsewhere in early life and were co-opted (perhaps for ideological or ethnic reasons) before returning to the target country. That is valuable to the sponsor as the sleeper's language and other skills can be those of a 'native' and thus less likely to trigger suspicion.

Choosing and inserting sleeper agents has often posed difficulties, as it is uncertain that the target will be appropriate some years in the future. If the sponsor government and its policies change after the sleeper has been inserted, the sleeper might be found to have been planted in the wrong target.

In fiction, particularly science fiction, sleeper agents fall into two categories. The former is an extension of the real world sleeper agent where an enemy agent is substituted for a person already in a trusted position. The latter and more common category involve those who have been subjected to mind control techniques, such as drugs, torture, psychological conditioning, implanted devices, and even telepathic manipulation and then are either released or allowed to escape back to friendly territory. The sleeper agents are then used by enemy forces to spy, to conduct sabotage, to assassinate certain targets, or for other operations the enemy has in mind for them. During these outbreaks, the sleeper agent normally does not know what is being done.

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