There's a spoiler heavy interview with the DEXTER show runner over at TVGuide.com that you can check out at this link. In it we find out a lot more about Yvonne's character:
"She plays this woman named Hannah, who took off from this small rinky-dink Florida town and ran off with this older guy and they went on this wild killing spree. So when they got caught, she turned state's evidence on the boyfriend, he went to jail for life and she started a new life. Years later, she's in her 30s and she will intersect with Dexter."
There is more info about her character in the article. Follow the link above for more.
So, what do you think? Are you more or less excited to watch?