A walk-in agent is an individual who voluntarily offers to conduct espionage. Specifically, a "walk-in" is an agent or a mole of a government who literally walks into an embassy or intelligence agency without prior contact or recruitment.
Famous quotes containing the words walk-in and/or agent:
“With four walk-in closets to walk in,
Three bushes, two shrubs, and one tree,
The suburbs are good for the children,
But no place for grown-ups to be.”
—Judith Viorst (b. 1935)
“... in doing our psychology, we want to attribute mental states fully opaquely because it’s the fully opaque reading which tells us what the agent has in mind, and it’s what the agent has in mind that causes his behavior.”
—Jerry Alan Fodor (b. 1935)