WARNING: This article contains spoilers for Once Upon a Time

ABC's Once Upon a Time midseason 3 premiere will put a Wizard of Oz spin on classic fairy tale characters with the help of the show's newest cast member, Glinda the Good Witch.

Yesterday, TVLine reported that the Sunny Mabrey was cast as Glinda the Good Witch of the South, the archrival of the Wicked Witch, played by Rebecca Mader (Lost).

"Mabrey's Glinda has been described as elegant, warm and benevolent, as well as wise, clever and shrewd," the website said. "However, years of isolation have made her lonely and cautious -- though at her core, she is a steadfastly filled with optimism."

Mabrey is known for her roles on TNT's The Memphis Beat, Lifetime's The Client List and 2006's Snakes on a Plane.

TVLine also reports that Rapunzel will appear in the episode 14 of the season. The long-haired princess will be played Alexandra Metz, who is known for playing Katie in The CW's The Originals. She is reportedly signed for one episode as of now.

In addition, Rose McGowan will reportedly reprise her role as young Cora, the mother of Regina (Lana Parrilla), in episode 18. Plus, to make season 3 even more family-oriented, viewers will learn more about King Leopold, Snow White's (Ginnifer Goodwin) father.

"... we'll be treated to a flashback starring young Prince Leopold," E! News said. "Did we mention that he's single in these scenes? Get ready to watch the charming lad's quest to find a suitable queen for the kingdom."

All these new characters are exciting, but the second half of season 3 will not end happily ever after, as another main character is set to die.

"The character dies for real," Eddy Kitsis, series co-creator, told TVLine.

The Once Upon a Time midseason premiere airs March 9, 8/7c on ABC.