When she showed up at the Metropolitan Opera on Friday for the opening of the new opera “Marnie,” Tippi Hedren wore an elegant, glittering floor-length gown. In bright red.

“I thought, I’m going to wear it,” Ms. Hedren, 88, who starred in Alfred Hitchcock’s 1964 film version of “Marnie,” said with a mischievous smile, “and see if anybody gets it.”

Plenty did, to her delight. In the film, the color red — seen in a bunch of gladioli, or an ink stain on a white blouse, or a jockey’s silks — sends Marnie into paroxysms of terror, triggering memories of the childhood trauma that turned her into a deeply troubled kleptomaniac.