Michelle Trachtenberg

Michelle Trachtenberg will join the cast of Weeds in Season 7, Showtime announced Monday.

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Trachtenberg, best known for her roles on Buffy the Vampire Slayer and Gossip Girl, will play Emma, a smart and sexy pot-dealing rival to Nancy (Mary-Louise Parker). Silas (Hunter Parrish) also finds himself attracted to Emma, natch.

The 25-year-old actress will appear in two episodes this season, which debuts Monday at 10/9c on Showtime.