once upon a time giancarlo esposito season 4 'Once Upon a Time': Giancarlo Esposito returning in Season 4 premiere Another “Revolution” star is coming to “Once Upon a Time” … but this time, viewers already know who he’ll be playing.

Giancarlo Esposito is set to return to ABC’s fairytale drama in the Season 4 premiere, TVGuide.com reports.

Esposito was last seen on “OUAT” as Sidney Glass, a.k.a. the Magic Mirror, locked away in the basement of Storybrooke’s hospital. Will he return with a vengeance?

Esposito’s former “Revolution” star Elizabeth Mitchell was also recently cast on “OUAT,” though her role is a bit more secretive. The only details revealed about the “Lost” alum’s new character is that she is a “possibly malevolent” person who has ties to “Frozen” sisters Elsa and Anna.

The “OUAT” Season 4 premiere, titled “A Tale of Two Sisters,” will introduce Storybrooke to the world of Disney’s big hit movie “Frozen,” with new characters Anna (Elizabeth Lail), Elsa (Georgina Haig) and Kristoff (Scott Michael Foster). No word yet on whether fans will also get to meet a live-action Olaf.
“OUAT” returns this fall on ABC.
Posted by:Sydney Bucksbaum