Alison has trouble dealing with her mom's death, and her friends must go along with her newest lie. Meanwhile, Spencer and Emily try to piece together info about Jason; and Hanna questions her own identity in the wake of Alison's return.

Alison returns to school with her chin up and a goal of righting past wrongs, but Mona and her crew are not in a forgiving mood. Meanwhile, Caleb comes back to town, and so does an old enemy.