The Gossip Girl cast has offered only vague details about her appearance, but Lady Gaga herself recently teased her upcoming cameo on the show next Monday.

"First of all, my sister's a huge fan, and she's 17 years old. She was like 'Oh my God, you have to do it,'" she told MTV of her eason for appearing on the CW hit.

"And I'd seen it. It's a great show."

We doubt the cameo will feature Lady Gaga unmasked. Expect elaborate costumes - and not your standard run-of-the-mill musical guest star appearance.

"I hate most TV show performances, because they kind of come in out of nowhere," she said. "It has nothing to do with the story and nobody cares."

What does she have in mind instead?

Lady Gaga made sure her Gossip Girl appearance was unique.

Rather than showing up on the set for a day, doing her thing and going home, Gaga met with producers to ensure she could do a performance she loved.

"I was like, 'Look, the reason I want to do this is because I'm trying to say something that is not exactly mainstream. So, if I can say it on your show, that would be, like, a real coup d'état for me as a performance artist.'"

Wonder what that could mean ... that's she's a hermaphrodite?

Okay, that's not gonna happen. But what she the result is a "crazy performance art" piece in which "I am the narrator behind what's been going on with the Gossip Girl characters and make the song part of the moment."

Now that should be something. Give her credit for uniqueness.

Here's a promo of Gaga's Gossip Girl visit ...

Lady Gaga Gossip Girl Promo