A letter dated to the eighteenth century BC sent by a servant to Zimri-Lim, the king of Mari, details a system of long-distance signal fires, thought to be the first ever in use. 

In 480 bc, with the Persian army on the cusp of defeating Greece, Athenian general Themistocles sent a trusted slave to convey a message to Persian king Xerxes; the note professed allegiance to Persia and reported many Greek ships prepared to defect. The Persians, acting hastily on this false intelligence, sailed into the Strait of Salamis, where the Greek fleet was waiting and gained a decisive victory. 

To label a program conceived in 2007 that declared as its purpose the tracking of “every user visible” on the Internet, collected data from over a trillion Web events in a repository called the Black Hole, and targeted sites broadcasting recitations of the Qur’an, the UK Government Communications Headquarters chose the name Karma Police, after a song by the band Radiohead whose chorus is: “This is what you’ll get / when you mess with us.” 

Charles d’Éon de Beaumont went to Russia in 1755 as a secret correspondent of French king Louis XV. Disguised as a woman, he obtained an appointment as reader to a Romanov empress; he returned for a mission the next year dressed as a man. By the 1770s speculation about his gender reached such fervor that odds were quoted by London brokers. An 1810 postmortem finally confirmed that he was anatomically male; Marie Cole, his companion of fourteen years, reportedly “did not recover from the shock for many hours.”

About the first spy film, made in 1898, almost nothing is known besides its name, Execution of the Spanish Spy. Made two years later, Execution of a Spy was a twenty-seven-foot reel showing a firing squad executing a spy in a military prison. In The Female Spy, from 1906, a woman is tied to a horse by her hair and dragged behind it.