The thriller masterpiece had all the elements of a Hitchcock suspense murder mystery - a deadly love triangle, a MacGuffin (latch-keys), a stagebound set and dialogue-rich script, another ofHitchcock""s brief cameo appearances, and an intriguing plot question - "Will he get away with it?" (not ""Who-dun-it?"").The film was also interpreted as an allegory of the US"" involvement in the Vietnam War - as the men (the US military) intruded into a foreign world (Southeast Asia), and found it was raped or confronted by wild forces it couldn""t understand or control.The setting of the film is among the privileged upper class society in Philadelphia.Hepburn""s character, a self-willed young aristocratic heiress (nicknamed ""Red"" by her ex-husband), is on the verge of a second marriage.When Edna heard something, she went to look for Harold and was spooked by a white rat.From behind, a hand grabbed her mouth, and her own previously-missing knitting needle was pierced into the back of her head(# 2 death), causing her to gag and slowly fall dead.