Shadows of Intrigue: 57 Thrilling, Gripping Mysteries from the World of Espionage

Broadly speaking, a spy is someone who engages in secret investigative work, gathering confidential intelligence or carrying out acts of sabotage against an enemy or competitor to benefit the side they serve. Spies are also known as agents or undercover operatives.

One of a spy's main duties is to obtain intelligence through illegal or legal means, in secret or in public. They may also engage in covert activities such as subversion, assassination, kidnapping, bombing, psychological warfare, and sabotage. They are dispatched or recruited to uncover secrets and intelligence or to carry out acts of sabotage.