'Once Upon A Time' Season 4 Spoilers: Will The Wicked Witch Zelena Return? Plus 13 Other Juicy Details

1. Episode 16 is said to be focused solely on Rumplestiltskin. Co-creator Adam Horowitz also teased via Twitter that the episode will be titled "Best Laid Plans" and written by Kalinda Vasquez and Jane Espenson.

2. More episode titles were revealed for the second half of season four of "Once Upon a Time." These include "Darkness on the Edge of Town," "Unforgiven," "Enter the Dragon" and "Poor Unfortunate Soul."

3. Showrunner Eddy Kitsis teased season 4 spoilers for "Once Upon a Time" during an interview with TVLine. "Rumple is absolutely the Big Bad," he said. "And I would also say that the three women can more than hold their own. It's a very formidable team of evil coming our way."

4. Cartermatt website said that Robin Hood, Sean Maguire, will make his anticipated return in the "reasonable near future." Maguire himself admitted during the Magic city Comic Con in Miami that he will appear soon in the ABC fairytale drama.

5. While Rumbelle shippers have doubts that Rumple and Belle will end up together the creators of the hit ABC series feel differently. In a recent interview with Entertainment Tonight Horowitz said, "What I'll say about this, in all seriousness for the Rumbelle fans, is that definitely Rumple and Belle are not over." Horowitz added that the mid-season finale was just a chapter in the "OUAT" story, and he tried to appease fans, saying, "We're telling a larger story and there are more chapters to come."

6. Horowitz also talked about Emma and Captain Hook saying, "As far as Captain Swan shippers are concerned, I would say that the relationship between Emma and Hook is something we've been developing for a while and we're going to continue to develop it," He also added that Emma and Hook will have "personal challenges" to face individually.

7. We didn't see a lot of Snow and Charming in the first half of season four of "OUAT" but Horowitz says that will change. "Oh we're going to get much more Snowing in the second half and we're very excited. We are going to get some really fun flashbacks with them and realize they have a really interesting connection to the Queens of Darkness," Horowitz said.

8. According to Hypable Patrick Fischler will join "Once Upon a Time" season four for a recurring role as a peddler. Fischler’s character is confirmed to appear in both Storybrooke and the Enchanted Forest portions of the season’s second story arc.

9. Eion Bailey who played Pinocchio in the first couple of seasons of "OUAT" is said to return to the series in the episode titled "Enter the Dragon." More than likely he will appear in a flashback scene of the episode.

10. "The Originals" Sebastian Roche has been cast in the role of King Stefan for "OUAT" season 4. He will be joining as King Stefan who is Aurora's father. It has been said that King Stefan has a complicated past with Maleficent who will have a big role to play in the second half of "OUAT."

11. Another big casting annoouncement was Ernie Hudson who will take on the role of Ruler of the Sea and Ursula's father Poseidon. It is said that he will show up in episode 15.

12. In an interview with Entertainment Weekly Horowitz and Kitsis revealed that Archie (Raphael Sbarge) should be “worried” about his Dalmatian named Pongo now that Cruella has been named a major player in Season four.

13. The co-creators also teased to EW that Hook (Colin O’Donoghue) will be hungry for revenge on Rumple, and that everyone’s favorite pirate might have history with yet another villain. When asked if Hook has a “past” with Ursula, Edward Kitsis replied, “can’t say.” However, Ursula being from the sea and Hook being a pirate the pair having a complicated past seems more than plausible.

"Once Upon a Time" season four, episode 13, “Darkness on the Edge of Town,” returns Sunday, March 1 at 8:00 p.m. ET on ABC. Make sure to tune in!