ABC’s latest batch of Once Upon a Time stills introduce two new characters that may be the catalyst for Zelena’s plan to unfold. Preview the images and read the full synopsis for “Kansas” here!

The house has fallen in Oz! Since the introduction of Zelena to the mixed up world of Once Upon a Time, Dorothy was bound to make an appearance. But will the Dorothy from the minds of Horowitz and Kitsis resemble the strong-headed girl from L. Frank Baum?

Labor pains are set to arrive on this week’s episode! The second offspring of television’s truest love is set to make their debut. In the images below the happy couple’s bliss is interrupted by an unwelcome visitor.

‘Kansas’ Synopsis

With Mary Margaret in labor and due to give birth at any moment, the residents of Storybrooke go on high alert in an attempt to ensure that Zelena doesn’t try to steal her newborn baby for use in her ultimate game plan to turn back time and change her destiny — while obliterating Regina’s existence. Meanwhile, in the land of Oz of the past, Glinda tries to convince Zelena to fight her evil tendencies and join her and her sister witches as a protector of Oz. But the appearance of a young girl from Kansas could turn out to be her undoing.

Hopefully, Emma finds a way to keep her powers long enough to use them against Zelena and save her family’s existence. No viewer wants to see the Charming couple lose their child a second time.

This week also marks Henry’s return to the life he didn’t know he lost. It will be interesting to watch him take in the latest danger to his family and not be the person hold hostage!

Watch Once Upon a Time season 3, episode 20 “Kansas” Sunday, May 4 at 8 p.m. ET on ABC.