Tilda Swinton Naps in Glass Box for MoMa Installation

Tilda Swinton David Bowie - P 2013
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Tilda Swinton David Bowie - P 2013

The Oscar winner surprised museum visitors with the unannounced appearance, which will be repeated at unspecified dates.

Tilda Swinton knows how to give an arresting performance – even in her sleep.

The actress surprised guests visiting New York’s Museum of Modern Art on Saturday by napping in a glass box as part of an art installation, Gothamist reports. Crowds gathered to catch a glimpse of the Oscar-winning actress, whose appearance was unannounced. (Photos can be found here.)

"Museum staff doesn't know she's coming until the day of, but she's here today," a museum source said. "She'll be there the whole day. All that's in the box is cushions and a water jug."

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Saturday was her first time performing the piece at MoMa. Swinton was located by the ticket collectors, but the location may be changed in the future.

Swinton first performed the piece, called “The Maybe,” in 1995 in London’s Serpentine Gallery. She collaborated with artist Cornelia Parker on the project and went went on to perform it at the Museo Barracco in Rome.

“An integral part of The Maybe's incarnation at MoMA in 2013 is that there is no published schedule for its appearance, no artist's statement released, no museum statement beyond this brief context, no public profile or image issued,” the museum said in a statement. “Those who find it chance upon it for themselves, live and in real—shared—time: now we see it, now we don't.”

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Swinton, who was named the new face of Chanel last month, has been embracing her artistic side as of late. She honored David Bowie in a stirring speech Wednesday at London's Victoria and Albert Museum.