There's a serial killer stalking this season of Once Upon a Time, and now we finally might know why he's got a taste for witches.

Ever since someone started hunting Mother Gothel's (Emma Booth) coven down one by one, we knew it was only a matter of time before poor Drizella's (Adelaide Kane) found herself in the killer's crosshairs. That's exactly what happened in tonight's episode, but what we never could have expected was the true identity of this murderer.

The episodes' final moments saw Jack (Nathan Parsons) loading up his car after a bro's night out with Henry (Andrew J. West) and Hook (Colin O'Donoghue). In addition to some automotive necessities the trunk of Jack's car also contained two boxes of chocolate — the serial killer's calling cards — and the mask the killer used to attack Drizella earlier that day. Talk about a smoking gun...

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So far, Jack's been kind of a wishy-washy character in the narrative. He was Henry's bestie in the Enchanted Forest, Lucy's fake curse dad, and a relatively cool guy, but not a lot else going on. Now though, we have to cope with the fact that Henry's closest pal is actually a witch-killing psycho!

He may have another identity all together though...

In Drizella's flashback, we saw her meet Gretel (Sara Canning), who told Drizella the bleak tale of her and her brother Hansel's capture by a witch who tried to eat them. While Gretel walked away mostly unscathed, she said the experience changed her brother turning him into a totally different person. Could that person perhaps be Jack? The theory makes enough sense, especially when you consider he's got to have a pretty good reason for knocking off witches. Childhood trauma may not excuse his murder spree, but it could certainly explain it.

The only way to know for sure is to get a peek at Jack's arms. Gretel mentioned that he had severe burns on his arms from their gingerbread house encounter, so roll up those sleeves, Jack!

Either way, there's another implication here. Jack walking around killing witches means that he's no longer cursed, which begs the question: Who woke him up?

Once Upon a Time airs Fridays at 8/7c on ABC.

Adelaide Kane, <em>Once Upon a Time</em>Adelaide Kane, Once Upon a Time