Marina Abramović is a Serbian performance artist based in New York whose work explores the relation between the performer and the audience.
Ulay is an artist who based in Amsterdam and Ljubljana who is known for his radical actions and Polaroid work from the seventies. His photo experiments are still talked about among other artists.
Sometime in the 70s, Marina and Ulay dated each other but they eventually parted ways. Literally. They went to the opposite ends of the Great Wall of China, met somewhere in the middle, embraced each other one last time and never met again.
But in 2013, almost 30 years later, a Marina held a live art performance where she sat in silence with strangers for a minute each, in walked Ulay as one of the "strangers". The change in her expression revealed her joy in seeing him.
Check it out.
Source - MrHIBTB