We've already had hints of Jason's shadiness during Season 1. In Season 1, Episode 15, “If At First You Don’t Succeed, Lie, Lie, Again,” Jason spied on the girls from Alison’s old bedroom, even though Maya (Bianca Lawson)'s family had been living there. When a fan tweeted at Marlene asking why Jason was in Maya's room, she replied: “Good question. To be answered first episode, second season.” Either he broke into Maya’s house, or he’s staying there during the investigation into Alison's murder. Sketchy.
If that isn't enough, we also have our suspicions that Jason is the new guy Aria will crush on during her break from Ezra (Ian Harding). If that's true, things will definitely get complicated. We can't wait to find out more!