CBS has shared a new promo and stills for this week’s episode of The Big Bang Theory, which hints at a glamorous dinner and some kind of secret. (Ooooh.) Minor spoilers ahead.

A new preview has been released for Thursday night’s episode of The Big Bang Theory (as well as that of Two and a Half Men) titled “The Closet Reconfiguration.” It looks like the geeky gang will be indulging in a bit of grown-up sophistication this week (well… except for Sheldon), is a special occasion imminent, perhaps? Check out the new promo right here:

It’s hard to imagine that Penny has many secrets left in that dress (though she looks like a knockout, of course) but what could Sheldon have in that bag that Penny is so afraid to let out? The still photos released from “The Closet Reconfiguration” don’t offer much by way of a hint; instead, they seem to focus on Howard and Bernadette’s deceptively domestic plot line. Check out the photos below:

[scrollGallery id=1226 start=0 autoScroll=false height=400 thumbsdown=true]

CBS’s official summary for “The Closet Reconfiguration” also prioritizes Howard and Bernadette’s story, which may bring on more emotion than just the terror of messy closets.

Howard struggles with whether or not he should open a letter from his father, and Leonard and Penny throw a “grown-up” cocktail party at the apartment.

And for even more of a Big Bang Theory fix, look into the show’s panel at PaleyFest 2013, which will air live in movie theaters across the country on Wednesday night.

The Big Bang Theory airs on Thursdays at 8 p.m. on CBS.