Bridgeport, Connecticut: Between a detention centre and a post office here, there is a large, unremarkable building on a corner. Other than a few parked cars near a loading dock, there is not much life outside its off-white walls.

But walk through the rickety front door and up the concrete stairs, and what is inside makes the gritty old Times Square of the 1970s look innocent: thousands of boxes filled to overflowing with sexually explicit films and artefacts.

Joe Rubin, founder of Vinegar Syndrome, a company that restores and releases classic X-rated movies, rummages through unsorted material. Credit:New York Times

Welcome to the home of Vinegar Syndrome, founded in 2012 by Joe Rubin and Ryan Emerson to catalogue, restore and help release old X-rated films for the home video and theatrical markets. ("Vinegar syndrome" refers to what film smells like when it starts to decay.) The company, which takes up only about a third of the 4366 square-metre building, plans to introduce a new generation to lost and forgotten films from what is considered the golden age of American hard-core filmmaking, roughly 1969-86.

"Yes, the films are X-rated," Emerson said. "But many of them are interesting and fascinating once you get into them. These films are time capsules."