Britney Spears stands on table in uber-mini dress at 'The Ellen Show'

Work, Brit!

Britney Spears made a surprise appearance on "The Ellen DeGeneres Show" on Friday, where she announced that she was making a big announcement on October 18.

For her appearance, Spears rocked an burgundy uber-mini dress with ruffled sleeves, a choker collar and a plunging neckline. Her signature blonde locks cascaded down as she made her way out onto the stage to deafening cheers from the audience.

"I actually have a huge announcement to make," Spears said as she sat down. "My announcement is actually that I have an announcement. I can't announce the announcement until October 18th. [I'm] a little early."

See her look in the gallery below:

DeGeneres added that Spears will be making said announcement on Ellen's YouTube channel next week.

Spears took to Instagram on Friday to share a little behind-the-scenes moment from her time at Ellen's studio, posting a video of herself standing on a wooden coffee table in her dressing room.

"Hi guys what's up on 'The Ellen Show' today and I'm getting a little cuckoo that's why I'm standing on this table," she said in the cute clip. "I have no idea why. Anyways, I'm excited!"

Her rare promotional appearance on Friday also featured a mini "Mickey Mouse Club" reunion with Ryan Gosling, who appeared on the episode to promote his new film, "First Man." Reflecting on his time on the Disney show as a tween, Gosling called Spears and fellow star Christina Aguilera "freakishly talented."

Stay tuned for what Britney Spears is gearing up to announce on October 18!

See more photos of Britney Spears through the years: