‘Once Upon A Time’ Season 4, Episode 17 Spoilers: Robin Hood Becomes A Thief For Greater Good?

 "Once Upon a Time" season 4, episode 17 won't be aired until the second week of April, but spoilers are already filtering in revolving around Robin Hood and the Wicked Witch of Oz.

The teaser clip shows Robin Hood and Rumple making a journey to Oz and they will run into Zelena aka the Wicked Witch, who's more powerful than ever.

As Robin Hood is about to let his arrow fly, he's confronted by three Zelenas (with two other clones) who then asks him, "You think you can kill me? Don't make the wrong choice."

The obvious question therefore is, how did the Wicked Witch come back from the dead? And how is it that she becomes more powerful than ever?

There's also the question of Emma being in danger of going to the dark side after learning the truth about her parents' connection with Maleficent.

Colin O'Donoghue, who plays Captain Hook, talked about Emma's potential for darkness in an interview with Entertainment Tonight.

"At the moment, he's trying desperately to be there for her with all the stuff she's going through with Mary Margaret and David, and he's trying to help guide her," he said. "He's lived with darkness, and he's trying to use his past experiences to try and help guide her as best he can. To try to be a good person and stay on the right path. So at the moment, I would think that he's just trying to help her be The Savior and try and be supportive of all of that. If she ever let the darkness in, Hook loves her and I'm sure he'd do his best to keep loving her."

The synopsis offers a lot of spoilers for "Once Upon a Time" season 4, episode 18. It reads, "Emma is still reeling after learning the truth of her parents' history with Maleficent, but she must focus on finding the Author, who is running loose in Storybrooke, before Gold does."

"When Gold's quest for his happy ending grows more urgent, he blackmails Regina into helping him. In a Fairy Tale Land flashback, Robin Hood learns what it means to be an honorable thief when he accepts a proposition by Rumpelstiltskin to travel to Oz to steal a valuable magic elixir from the Wicked Witch," the story description added.

Watch out for more "Once Upon a Time" season 4, episode 17 spoilers which will be published here when they become available. "Heart of Gold" will air on April 12 on ABC.