Warning: This article contains spoilers for Once Upon a Time Season 2, Episode 5: “The Doctor.” Turn back now if you haven't seen it and wish to remain spoiler free.

The preview for Once Upon a Time Season 2, Episode 5: “The Doctor” basically revealed that the mysterious Dr. Whale (David Anders) was Dr. Victor Frankenstein back in Fairytale Land. But what exactly does that mean? The episode itself filled us in on his complicated history.

As we all know, years ago in Fairytale Land, Regina's (Lana Parrilla) evil mother Cora (Barbara Hershey) killed Regina's True Love Daniel (Noah Bean), because Regina was going to run away with him.

Well, it turns out that Regina, devastated and unable to move on, decided death wasn't going to keep her apart from her love. She kept Daniel's body preserved with a spell, in the hopes that she could find a way to bring him back. Fortunately for her, Jefferson (Sebastian Stan) knew of a person from another land who could help her. Enter Whale, AKA Frankenstein.

Although Jefferson called him a "wizard," Frankenstein called himself a "doctor." He had yet to actually bring someone back from the dead, because the key ingredient he needed could only be found in Fairytale Land: one of the magical hearts ripped out of someone's chest. He agreed to try to bring Danial back if Regina could get him the heart.

Regina took Frankenstein to Cora's creepy vault of hearts, and told him to take his pick. Frankenstein appeared to perform his Frankenstein-y surgery, but failed to revive Daniel. Regina was heartbroken, and that final loss of Daniel is what pushed her over to the dark side.

The biggest twist? It turns out Rumplestiltskin orchestrated the whole thing, with Jefferson's help. Frankenstein didn't really try to bring Daniel back at all, intentionally pushing Regina over the edge in return for a heart from Rumple. Frankenstein wanted the heart to try to bring his brother back in his own world. Though, as he tells Gold in Storybrooke, it didn't go well.

In present-day Storybrooke, Archie Hopper (Raphael Sbarge) encourages Regina to move on from Daniel, whose enchanted body she has brought to Storybrooke. But before she can do anything, Whale steals the body and one of Regina's heart, and brings Daniel back. But — you guessed it! — he's a monster, and attacks Whale! Whoda thunk?

In the end, Regina connects to the newly revived Daniel long enough for him to beg her to let him go, telling her the best way to honor him is to learn to love again. He dies, again, as Regina weeps.

Catch the next new episode of Once Upon a Time on Sunday, November 4 at 8 p.m. ET/PT on ABC.

Rebecca Martin is an editor at Wetpaint Entertainment. Follow her on Twitter @BeccaMartin47.

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