To celebrate 100th birthday of Grand Central Terminal, Arts for Transit commissioned Improv Everywhere and a group of 135 performers to surprise travelers on February 1, 2013, the official Centennial of the building. Equipped with flashlights and cameras, the group illuminated the grand windows on the West façade of the historic Terminal building with simple, impactful choregraphy. The surprise performance engaged thousands of passersby on the Main Concourse with a luminous shower of light, creating a carnival atmosphere in the city’s historic indoor town square. The spectacle was filmed by a 5-camera team and a YouTube video was produced generating over one million viewings in the first week, sharing the celebration around the world. Grand Central Lights highlights the historic and iconic architecture of a beloved landmark while marking its centennial with a contemporary, performance-based intervention, bringing delight and spontaneity to one of the most storied public spaces in the nation.