A case of mistaken identity taken to the extreme when witty and charming advertising executive Roger Thornhill (Cary Grant) unwittingly falls in with a ruthless band of foreign spies. The head spy, Philip Vandamm (James Mason) insists that Thornhill is in fact, CIA agent George Kaplin. Unbeknownst to all, including Thornhill, Kaplin is a fictional agent that the CIA invented to bait and trap the spies. While the CIA is trying to figure out a way to get the spies off of Thornhill's tail, Thornhill is subjected to threats at gunpoint, a staged car crash of which he survives, a harrowing airplane chase, and a perilous pursuit across the faces of Mt. Rushmore. Of course, all of this wouldn't be half as interesting without a little love interest, a woman Thornhill meets during his adventures named Eve Kendall (Eva Marie Saint). But in a world where Hitchcock is king and calamity abounds, nothing and nobody is as they first seem.