Everybody likes being let in on a secret. The problem with secrets is that very few people can keep them and some are simply so good they must be told. Here’s one you need to know: The Posies, the American power pop group that ruled the charts in the late ’80s and ’90s, are playing in Richmond on Saturday, Oct. 8, between 6-10 p.m. What remains a mystery is where that show will be. Coming to town as part of its Fall Pop-Up Tour, the band doesn’t reveal the location of the gig until the day before it plays. The only way you’ll find out is if you’re one of the lucky few to get a golden ticket. A limited number will be available and they cost between $20-$100. To get yours, visit theposies.net.