Tonight's episode of Gossip Girl continued rolling out the cameos that have come to define the show's fourth season. Last week gave Tim Gunn. This week? A chocolate-covered Rachel Zoe and Robyn.

The fun starts at Blair's birthday party. It legitimizes itself with the presence of Bravo reality stars!

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Next, Swedish pop sensation Robyn shows up with a tape of Blair drunkenly singing karaoke. The party takes a turn for the chaotic as Blair tries to stop the embarrassment.

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Later, Robyn's music accompanies one of the year's most intense and expected reunions as Blair and Chuck meet in the dark for some hateful loving.

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What does this mean for Chuck and Blair? How will they balance their hate with their undeniable sexual chemistry? How many more karaoke tapes of Blair does Robyn have?