It is considered a "superhero nightclub" but, really, anyone can be invited.
In 1995, the same year that Grond was created, a former villain named Lewis Frey decided he needed to do right after getting out of prison. The once and former "Masquerade" opened a club in the Renaissance Area of Millennium City, which he called "Club Caprice". The club was supposed to be "exclusive to Champions and heroes", as a place to go where heroes can just meet.
Sadly, this idea didn't hold up too well as the heroes were immediately suspicious of known supervillain creating a place "just for them".
So Lewis decided to open the club up for everyone, but with one caveat: everyone had to dress like a superhero.
The idea was a hit. Heroes and civilians would dress up in costume and nobody would be the wiser as to who was a hero and who wasn't.
Eventually the code was loosened a bit when it came to the new lounge area, which resembled a Roman assembly hall. But the dance floor section still kept the costume requirement until only recently.
Club Caprice is still in operation today, open 24/7/365.
Club Caprice was first seen in "The Lost Adventures of Galatea Future" #4.
Markman Gold is often there to get new clients and to hassle old ones.