On a recent Friday night, a small group of people lined up in a cinder-block hallway inside an unmarked entrance to Paddles, a club on West 26th Street. Two men in their 60s were discussing real estate and a few women in their 20s were sending last-minute texts before going down two flights to the subterranean space.

Paddles is not another trendy table tennis emporium, but a “safe space” to live out erotic fantasies, specifically BDSM (bondage/discipline, domination/submission, sadism/masochism), OTK (over the knee; in other words, spanking), and an alphabet soup’s worth of other sexual practices that, until recently, have gone largely unnoticed and undiscussed by the mainstream world.

But surely in part because of the blockbuster success of E. L. James’s “Fifty Shades of Grey” trilogy (65 million copies sold worldwide according to Publishers Weekly), people who are drawn to power exchange in sexuality and may refer to themselves as kinky are finding themselves in the spotlight as never before.

In February, “kink,” a documentary directed by Christina Voros and produced by James Franco, had its premiere at the Sundance Film Festival. (The Hollywood Reporter called it “a friendly film about lots of seemingly reasonable people who do terrible things to each other on camera for money.”) Phrases like “safe word” are increasingly part of pop culture; on the IFC hit “Portlandia,” one sensitive character said hers (“cacao”) even when her boyfriend is sleeping. On Showtime’s “Shameless,” Joan Cusack plays a kinky mother trying to manage the enthusiasm and pricey toy collection of her younger lover.