On May 11, Brittany Snow, Krysten Ritter, Andrew McCarthy and No Doubt take us on a wild flashback ride to the 1980s, where 17-year-old Lily Rhodes gets kicked out of her upscale boarding school and runs away to Los Angeles.

There, Lily (Snow) reconnects with her parents Rick (McCarthy) and Cece (Cynthia Watros of Lost fame), and sister, Carol (Ritter). This episode of Gossip Girl, "Valley Girls," doubles as the debut of the new '80s spinoff from the GG producers.

Meanwhile, back in the present day, Blair and Nate attend the prom together, but the evening doesn't turn out exactly as planned.

As you might expect, Chuck Bass has a little something to do with that.

Serena and Lily don't see eye-to-eye over Serena's recent run-in with the law. We know it involves Gabriel somehow, but what do you suppose she did?

In any case, here are some present-day photos from the May 11 episode (this is the episode after "The Wrath of Con," which airs next Monday, May 4):

Follow the jump for photos from the '80s portion of the episode ...

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