Unknown to most inhabitants of Equestria, members of an alien people have come to live among them. Also unknown is that they're there involuntarily, in the dark as to why and how they're there, transformed into members of the native species.
What many ponies do know, the ones who live in Canterlot at least, is that there's a new venue open in Equestria, very exclusive, but not for the rich elite, nor the cultural avante garde. In fact, there seem to be no rhyme or reason to determining who is allowed and not allowed in on the premises, and despite many petitions to have the discriminating bouncer fired, things go on as usual in this strange new club.
Shout out to billymorph for planting the idea for this story in my head with his own story, The Humans in Equestria Club.