It's the Halloween before Alison disappeared and where all of the secrets and lies began for Aria, Emily, Hanna and Spencer in "The First Secret," a special Halloween-themed episode of ABC Family's hit original series "Pretty Little Liars."

It's the Halloween before Alison disappeared and where all of the secrets and lies began for Aria, Emily, Hanna and Spencer in "The First Secret," a special Halloween-themed episode of ABC Family's hit original series "Pretty Little Liars."