A new promo for the upcoming second half of season 4 of ABC's Once Upon a Time aired during the Oscars Sunday night, with a chilling message regarding Emma (Jennifer Morrison).

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The new ad was a promotional trailer for season 4B of Once Upon a Time, with villains Maleficent (Kristin Bauer van Straten), Cruella de Vil (Victoria Smurfit) and Ursula (Merrin Dungey) taking prominence. The promo features Rumplestiltskin (Robert Carlyle) speaking in an ominous voiceover about his plans for the trio of villains and Emma.

"There are three ways to corrupt a hero. Three ways to tarnish a Savior," Rumple says, obviously talking about Emma. "For Cruella, Ursula and Maleficent to obtain their happy ending, they must find someone whose soul can be molded, someone whose heart is brimming with darkness, who's ready to walk on the dark side."

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The promo ends with Emma sporting a curiously evil look while surrounded by Maleficent, Cruella and Ursula. This suggests that the villains may cast her under their spell and get her to turn to the dark side.

It remains to be seen what will become of the show's leading hero but it's not looking good for her. It may be fun to see Emma turn to the dark side and display her magic powers through a darker lens though.

Once Upon a Time returns Sunday, March 1 at 8 p.m. ET/PT on ABC.

Watch the new promo for the midseason premiere of Once Upon a Time below: