The Insider.com

She's been an integral part of Pretty Little Liars since day one, but until this season, we simply didn't realize how centrally Jenna figured into Rosewood's overriding mystery.

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Sure there were hints here and there, but Jenna's central role in Alison's murder finally came into focus once fans were gifted with August's midseason finale and the Halloween special!

Breaking The PLL Code

But just who is the girl bringing Jenna to life? Learning all about actress Tammin Sursok was just one of my objectives when she stopped by TheInsider.com studios last week.

The other? Dig up as many spoilers about these last few episodes as possible! And you'll be pleased to know that both missions were accomplished!

Pretty Little Liars airs Mondays at 8 p.m. on ABC Family.