She isn’t.
Guest starring are Tony Perez as Valet, Giancarlo Esposito as Sidney/Magic Mirror, Jennifer Koenig as Queen of Hearts, Sebastian Stan as Jefferson, Ali Skovbye as Paige/Grace, Donald Adams as vendor, Roger Daltrey as Caterpillar (VO), Paul McGillion as Knave of Hearts, Laura Wilson as Mrs. Grace and Scott E. Miller as Mr. Grace.
http://www.ksitetv.com/once-upon-a-time/once-upon-a-time-episode-17-hat-trick-spoilers/12367
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