Must you love a script to portray it to its full potential? Not if you’re Cary Grant. Alfred Hitchcock’s 1959 film North by Northwestis a masterful cat-and-mouse thriller in which advertising executive Roger Thornhill, mistakenly identified as a government agent, is pursued across the country by foreign spies. Though Grant is his usual suave self, you might not know his convincing portrayal of a man caught in a maze of mistaken identity was partially authentic — the actor himself was genuinely befuddled about much of the film’s plot during production.