Barbara Hershey and Lana Parrilla

Think Barbara Hershey was scary as the psycho mother of Natalie Portman in Black Swan? Just wait until you catch her debut as Cora, the mother of the Evil Queen (Lana Parrilla), on the April 8 episode of ABC's Once Upon a Time.

"Girls say they'll never grow up to be like their mothers, but evil comes from somewhere," says executive producer Edward Kitsis. "Cora would look at the mother from Black Swan and think she was weak."

During Barbara's multi-episode arc, the series will flash back to show Snow White as a little girl and the Evil Queen as a young princess living with her fairy-tale family before her heart turned bitter cold. "You will finally find out why the Evil Queen hates Snow White," hints executive producer Adam Horowitz.

Adds Edward, Cora has "an interesting connection to Rumpelstiltskin and an agenda she does not like to veer from." Her past "is just hinted at this year," he says. "But we have major plans for Cora in the future."

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