The Grey's Anatomy alum will appear in the season finale as Charlie, the manager of the diner where Fiona (Emmy Rossum) starts working after her trip to jail. If you missed Sunday's episode — spoiler! — young Liam accidentally got his hands on Fiona's cocaine and overdosed, so she was arrested.
Morgan most recently starred on the Starz period drama, Magic City.
Shameless airs Sundays at 9/8c on Showtime.
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