Today, a Cuban artist will walk the streets of Philadelphia dressed in a suit made of mud and nails. The Barnes Foundation invited the controversial artist Tania Bruguera to reprise her politically charged performance piece from 20 years ago.

The day before her planned walk, she sat on the floor of a room at the Barnes , pushing many hundreds of nails of varying size into blocks of foam, which would then be covered in a thick paste of white glue and dirt.

Those blocks form segments of a suit that will completely cover her from head to toe, making Bruguera resembling a primitive sculpture.

She is going for the look of a traditional South African power figure, a nkisi nkonde. Those are normally smaller dolls carved from wood, into which people drive nails. Each nail is a desire or promise the user intends to fulfill.

If the promise is not fulfilled, the spirit in the figurine will awaken and haunt the user.

For the first performance of "Displacement," Bruguera donned the suit and silently walked the streets of Havana, where such icons are widely recognized in Afro-Cuban spiritual practices. It was on August 13, 1998, which also happened to be Fidel Castro's birthday.

"Some work that I do needs a political context to be understood and enjoyed as a full experience," said Bruguera. "My work needs people to address something."

The current exhibition at the Barnes Foundation, "Person of the Crowd," is about art performed in public places over the last 50 years. On display is the original "Displacement" suit, with a video of that first performance. Subsequent performances in New York, Los Angeles, and Dublin, Ireland, have been essentially the same, but absorb different meanings depending on the particular political climate.

"In repressive political contexts, you learn how to create metaphors in order not to address what you need to say. Fear transforms into code," said Bruguera. "I wanted to challenge that, so I had to learn how to talk. How to narrate your own story, and give meaning to things on your own terms."

Later, Bruguera would learn to talk; her work became less symbolic, more vocal and explicitly political.

In 2015 she staged another public performance in Havana, "Tatlin's Whisper," wherein she set up a microphone in a plaza and invited anyone to say anything for one minute. The government - by then ruled by Castro's brother, Raul - immediately arrested Bruguera. The action provoked a worldwide petition calling for her release.

The incident also sparked a debate in the art world about the line between performance art and political provocation.

After the heat from "Tatlin's Whisper" died down, Bruguera did not initially want to revive her nearly 20 year-old dirt suit nailed with unfulfilled promises. She agreed to the invitation by the Barnes Foundation because it was in Philadelphia, where the promise of Democracy was born.

"That was why I said yes. I would never had done this piece again," said Bruguera. "But in Philadelphia, with the Constitution, all these historical elements - and this situation with Trump - I said, OK, I can give it a shot."

Bruguera will begin at the Barnes at 11AM, walking along the Parkway toward City Hall. She'll go all the way to Independence Hall if she can hold out long enough. As you can imagine: a suit made of dirt, glue, and nails is very heavy, and very hot.

"Oy oy oy, I don't want to think about it," said Brugeura while pushing hundreds of five-inch galvanized nails into foam. "If I think about it, I might not put it on."