Rachel Carr is a teacher at Constance Billard who befriends Serena, ruins Blair's chances of going to Yale, and sleeps with Dan. In "Carnal Knowledge," Blair, who made an enemy of Rachel in the previous episode after Rachel gave her her first "B" (on a Shakespeare paper) starts a rumor that Rachel and Dan are lovers. It isn't true—yet. Distraught over the false allegations, Rachel seeks Dan's comfort. Serena gets the wrong impression when she sees the two talking in a coffee shop, so she takes a mildly incriminating photo, which Blair presents to the Constance administration. Rachel is fired as a result. After breaking up with Serena, Dan shows up at Rachel's door to apologize for everything, but he and Rachel have sex instead—validating the slander. This happens just as the school decides to give Rachel her job back on grounds of inconclusive evidence. Rachel eventually leaves for Iowa after the school finds out about her secret relationship with Dan and her sabotage of Blair's admittance to Yale.
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