Before "Once Upon a Time" Season 4 took a short hiatus, Emma (Jennifer Morrison) discovered that Maleficent's (Kristin Bauer van Straten) allegedly dead child is actually alive, and she happens to be Emma's childhood friend Lily.

Recent reports announced that the role of adult Lily had already been cast, and it will be portrayed by "The Anna Nicole" star Agnes Bruckner.

According to Hypable, Lily had a rough time after Emma's parents Snow White (Ginnifer Goodwin) and Prince Charming (Josh Dallas) took her from Maleficent and sent her to the real world through a portal. After being adopted as a baby, Emma had a chance encounter with Lily when she tried to shoplift several groceries in a store when she was a teen. The two instantly became friends and ran away together for a couple of days, until Lily's adoptive father found them and took her home.

Now that Lily's true identity had been exposed, how will Maleficent's child deal with her new discovery? Will she unleash her dark side once she enters the Enchanted Forest and reunite with her mother?

Meanwhile, Emma must try to brush her anger for her parents aside to look for the Author (Patrick Fischler) before Rumpelstiltskin (Robert Carlyle) beats her to it.

It seems like Rumpelstiltskin will do everything to be able to track down the writer of all things that happen in Storybrooke, since he reached the point of blackmailing Regina (Lana Parilla) to help him.

But what could possibly be the Evil Queen's dark secret that Rumple is planning to use against her? Regina's evil antics had been divulged in the past, but Rumple managed to keep one that he could use in cases like this where he could take advantage of Storybrooke's wicked resident to do whatever he wants.

In an interview with Entertainment Weekly, executive producer Edward Kitsis shared that Regina's secret is "something entirely different and yet familiar at the same time."

Once Upon a Time Season 4 episode 18 titled "Heart of Gold" airs Sunday, April 12, on ABC.