In her documentary Cast In India, filmmaker and anthropologist Natasha Raheja travels to a dirt-floor factory in Howrah, India to show where and how our city's manhole covers are made. She told National Geographic in an interview earlier this year that the subject matter interested her because the objects "are an iconic and ubiquitous part of New York City’s urban landscape. I became curious about how these pieces of city anatomy are made. I wanted to learn more about the labor infrastructure concealed in the built infrastructure of our cities."

Her observational piece also shows the "disparate conditions that shape the geographies of production and consumption of everyday urban objects." Below, watch as barefoot workers stomp the shape into these 300-lb metal covers that we walk over every day.

The workers are unionized, according to Drive, and the film also shows "their struggle to negotiate a new contract with their employer. 'They are politicized and know they deserve more for what they do,'" Raheja noted.