Once Upon a Time exclusive: Giancarlo Esposito returning for 100th episode 

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Another day, another familiar face returning to

Giancarlo Esposito will reprise his role as Sidney Glass, a.k.a. the Magic Mirror, in the landmark episode, EW has learned exclusively. 

The last we saw of Sidney, he had aligned himself with the Snow Queen (Elizabeth Mitchell), who freed him in exchange for working against Regina (Lana Parrilla). 

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Details on Sidney’s return are being kept under wraps. Esposito joins the previously announced Barbara Hershey, reprising her role as Cora, and Robbie Kay, back as Peter Pan. The 100th episode is slated to air as the spring premiere in early March.

alum Greg Germann has landed a recurring role for the second half of he season. Details on his part are scarce, but TVLine reports that he’s playing a role referred to as “The Distinguished Gentleman.” He’ll first appear in the 100th episode. 

Once Upon a Time airs Sundays at 8 p.m. ET on ABC.

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