The former "Saturday Night Live" and "Kath & Kim" star reportedly is expected to play a new astronomy teacher and badminton coach, who also happens to be an alcoholic and prescription drug user.
"She becomes Sue's enemy," a "Glee" insider told EW.com, referring to Jane Lynch's bossy, manipulative cheerleader coach character Sue Sylvester.
Shannon's first episode is to air in May, the entertainment news Web site said.
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