Emma Watson had a bit of a wardrobe malfunction at the "Harry Potter and the Half-Blood Prince" premiere, but she doesn't seem too bothered by the mishap.

Watson was a guest on "The Late Show with David Letterman" Wednesday night, and Letterman asked what happened at the movie's London premiere, when a gust of wind blew open her dress, Marilyn Monroe-in-"The Seven Year Itch" style, and exposed her skivvies.

"I don't actually remember when this happened," the 19-year-old actress said with a slightly embarrassed laugh. "At least I'm wearing underwear."