The saying "The past will come back to haunt you" is never more true than for Aria, Spencer, Hanna and Emily. As the girls try to pay tribute to Alison's memory, the four friends are faced with unresolved issues. Aria has an unsettling encounter with her father's former mistress, Meredith. Emily is forced to see Toby Cavanaugh in a new light. Spencer is reeling in the wake of a vengeful Me