Tilda Swinton Sleeps In A Box at MoMA for "The Maybe" (PHOTOS)

Actress Tilda Swinton will be sleeping in a glass box in New York City's Museum of Modern Art as part of her "The Maybe" performance art piece, which first began in 1995 at London's Serpentine Gallery as a collaboration with artist Cornelia Parker.

Swinton, known for her roles in films like "The Lion, The Witch and the Wardrobe," will lie in the glass square whenever she wants, sporadically showing up to MoMA with little warning. Even museum staff won't be aware of her arrival until the day of, a MoMA source informed Gothamist. Each performance will last the entire day.

The Oscar-award winning actress arrived at the Museum on Saturday, with little press or information from hers or the MoMA's end. She climbed into the glass box, suspended about a foot in the air by black, metal legs, and laid on her side, clad in a denim button down shirt and dark jeans. She rested on a white linen pillow, small mattress, and had a water bottle resting beside her. See photos.

Her piece was met with some chuckles, as spectators took to Twitter with commentary on the decidedly odd performance.

"Despite all my rage I am still just a Tilda Swinton in a glass box," user AdamWolf77 tweeted.

"Tilda Swinton was on exhibit sleeping in a glass box at the MoMA," comedian Erik Bergstrom tweeted. "It was a sophisticated reflection of how tired and trapped viewers felt."

"I'm still kind of upset that Tilda Swinton is not laying eggs in a glass box at the MoMA," user lizbelsky said.

Blog Thought Catalog recently published an article called "22 Facts that Prove Tilda Swinton is the World's Most Fascinating Creature." Number one on the list? Her performance at the Museum of Modern Art.

Swinton will continue showing her piece for the duration of the year.