Last week was a busy week in the art world for Scottish actress Tilda Swinton. On Wednesday, she gave the opening speech at the V&A’s blockbuster exhibition ‘David Bowie Is’ and on Saturday she spent more than six hours ‘napping’ in a glass box for a performance art piece in New York's Museum of Modern Art.

It’s not Swinton’s first contemporary art performance. The live sleeping work, which is a collaboration with artist and friend Cornelia Parker, debuted at the Serpentine Gallery in London in 1995 and was repeated at the Museo Baracco in Rome a year later.

Titled ‘The Maybe’, the piece consists of Tilda Swinton remaining in a glass box for some six-and-a-half hours. She wore the same combination of light blue shirt and jeans as she did 18 years ago. The only notable difference was the addition of a pair of glasses on the mattress beside her. The performance will be an occasional feature at MoMA in the coming weeks.