The next episode of Once Upon a Time season 3 looks to be a horror-themed, based on the new promo.

Hook Tries 'True Love Kiss' Again on Emma in Future Episode?

The promo for the episode, which is titled The Tower, features the first introduction of Rapunzel (guest star Alexandra Metz), the long-haired fairy tale princess living in her tower. In the promo, Rapunzel cries out for help, and Charming (Josh Dallas) dutifully responds, but Rapunzel tells Charming that there's nothing he can do.

There is a mysterious hooded figure that appears at her tower, though the identity of the person (or creature?) underneath the hood is unknown.

Charming "Facing Ultimate Fears" in Rapunzel Episode?

There are also scenes featuring the Wicked Witch Zelena (guest star Rebecca Mader) holding Rumplestiltskin (Robert Carlyle) in a cage, which was revealed in Sunday night's episode. The Wicked Witch's plans going forward are "malicious," according to Lana Parrilla, who plays Regina.

"[Zelena] wants to hurt people for different reasons than the Evil Queen wanted to kill Snow White," Parrilla told E! Online in a Monday report. "Their costumes are very similar, but their intentions are very different, like they're fighting for different causes. She wants to hurt people for different reasons. She's wicked."

It was revealed in Sunday night's episode that Zelena and Regina are actually sisters, making this the latest family connection revelation. The two have the same mother, Cora, a.k.a. The Queen of Hearts.

Once Upon a Time season 3 airs Sundays at 8 p.m. on ABC.

Watch a promo for the next episode of Once Upon a Time below:

Tags: Once Upon A Time television ABC