Serena: Blair, we need your help with a scheme.
Dan: She can't. [pause] If you take on one more thing, you're gonna break.

Blair becomes so scatterbrained next week on Gossip Girl that she puts on two different shoes. Never thought we'd see the day, but in her defense, there's a lot going on!

Plan the perfect party, take down a tyrant AND sabotage Chuck and Raina?! That's a lot for anybody to juggle, even a Queen. There's multitasking and then there's this.

Also, another familiar face returns to New York ... for better or worse.

Check out this promo for "While You Were Sleeping" to find out who:

What do you think? Follow the jump for an extended version of the same promo and a Canadian version and share your comments. More sneak peeks to come soon ...

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.