Revenge Preview Clip: Emily Warns Jack to ''Be Careful'' in Episode 13

Emily Thorne may be in a serious relationship with Daniel Grayson, but it's clear her childhood sweetheart, Jack Porter, still has a place in her heart. Maybe a bigger place than she'd like, and one that could jeopardize her vengeance scheme. But she can't resist telling him to "be careful" in his relationship with the fake Amanda Clarke.