Dark Days is a documentary made by Marc Singer, a British filmmaker. The film follows a group of people living in an abandoned section of the New York City underground railway system, more precisely the area of the so-called Freedom Tunnel.
When he relocated from London to Manhattan, Marc Singer was struck by the number of homeless people he had seen throughout the city. Singer had befriended many in New York's homeless community and later, after hearing of people living underground in abandoned tunnel systems, he met and became close to a group of people living in The Freedom Tunnel community stretching north from Penn Station past Harlem.
After living with them for a number of months, he decided to create a documentary in order to help them financially. Singer had never been a filmmaker before, and saw the production of Dark Days as a means of gaining better accommodation for the residents of the tunnel.