Actress sleeps in box, Katherine Mathilda "Tilda" Swinton is an English actress known for both arthouse and mainstream films was sleeping inside the box. Visitors to the Museum of Modern Art in New York on Saturday had the chance to see an unusual performance: actress Tilda Swinton sleeping in a glass box. Photos of the "Burn After Reading" actress, posted on a web site called Gothamist, showed Swinton wearing shoes, a light blue shirt and dark blue pants, lying on white bedding with eyeglasses beside her. "Living artist, glass, steel, mattress, pillow, linen, water, and spectacles," said a description card of the performance called "The Maybe," according to a photo posted on Gothamist, a web site that covers New York. Kids watching Tilda inside the box A spokesperson for the museum could not be reached on Sunday, but the museum on Saturday tweeted a link to a story on the gossip site Gawker, about the performance art and added the note