The official episode description of the second season premiere was posted recently!

As the summer draws to a close in the Hamptons, Serena and Nate have everyone fooled into thinking they are a couple to cover up the fact that Nate has been hooking up with a married older woman and Serena has been secretly mourning her break-up with Dan. Blair returns from abroad with a hot guy on her arm, making a very jealous Chuck question his decision to leave Blair stranded at the heliport. Dan has spent the summer assisting a famous author, but decides to head to the Hamptons to see how things stand with Serena after a summer spent apart. While interning for Eleanor Waldorf’s company, Jenny sneaks an invite to a much-coveted Hamptons’ White Party at which Eric introduces her to socialite Tinsley Mortimer.

[Via Teamsugar]

[Tinsley Mortimer Wears Her Bag On Gossip Girl]