Dr. Sullivan (Annabeth Gish) is an intriguing character, and we're excited to see her back on Pretty Little Liars during Season 3B. Is she trustworthy, or is she just the latest in a long line of lying Rosewood adults? Hopefully we'll start to find out what she makes an appearance on Season 3, Episode 18: "Dead to Me." Read spoilers at your own risk! For more on Wetpaint Entertainment's philosophy on spoilers, click here.