Once Upon a Time Season 2, Episode 5: “The Doctor” was packed full of surprises, but one of the biggest was the revelation that in the past Jefferson (Sebastian Stan) knowingly helped Rumplestiltskin (Robert Carlyle) trick Regina (Lana Parrilla) into thinking Frankenstein (aka, Dr. Whale [David Anders]) couldn't bring Daniel (Noah Bean) back from the dead.

This revelation puts Jefferson in a whole new light. When we were first introduced to him, we learned that Regina intentionally left him behind in Wonderland. At the time, that seemed like a totally cruel, selfish move on her part — now it looks like it may be just another blow in an ongoing fight between Regina and Jefferson. Plus, now we have to wonder if his kidnapping Mary Margaret (Ginnifer Goodwin) and attacking Emma (Jennifer Morrison) was the product not just of his insanity after being stuck in Wonderland and Storybrooke, but a deeper cruelty.

But we're getting ahead of ourselves. Because the question is: Why did Jefferson help Rumple? We have three theories.

It was part of an important deal: This wouldn't be the first time Rumple got someone to do something awful in return for his help, so this is always a possibility. However, Jefferson's flippant attitude — for example, the way he joked about Regina being reduced to tears — makes us think this isn't the case. He didn't seem like a man with a lot on the line.

He was a mercenary: Right now, this is the theory we're leaning towards. In his first scene in this episode, we saw Jefferson give Rumple a crystal ball, and say he couldn't find the slippers Rumple wanted. We're thinking that's a reference to the Wizard of Oz (the "slippers" being the shoes the transport Dorothy back to our world at the end of the book). It seems Jefferson went to Oz for Rumple; in return, Rumple gave him gold. Jefferson also told Regina that he was a traveler who had made "enemies." This all adds up to the picture of a man who portal jumped for money, and probably didn't care too much about who he hurt as long as he gets his payout in the end.

This would also fit with what we've seen of Jefferson later in the timeline: If his travels were all selfish, it makes sense that he'd devote himself to a humble life after he accidently lost his wife — but it also explains why he was so tempted by Regina's offer of a payout in return for his help.

If this theory is true, it's likely Rumple just promised Jefferson a pile of gold in return for help in this ruse, and perhaps even has him on retainer.

He has his own motivations: Is it possible Jefferson had reasons for working with Rumple that go beyond Rumple's infinite supply of gold? With this show, anything's possible, though at this point we'd be hard pressed to come up with a specific theory about what Jefferson could want.

Why do you think Jefferson was helping Rumple? Let us know in the comments below!

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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