What is "sleeper agent"

n. A spy who is placed in a target country or organisation, not to undertake an immediate mission, but rather to act as a potential asset if activated.

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. Sleeper agents are popular plot devices in fiction, particularly in espionage fiction and science fiction.

Sleeper Agent was an American band from Bowling Green, Kentucky. Their debut album, Celabrasion, was released on September 27, 2011, following the digital release of the album in August. Rolling Stone magazine noted the group as a "band to watch" prior to the LP's release.