With Lucas missing and questions surrounding what happened out on the lake, Hanna can barely catch her breath. With Caleb determined to find his friend, Hanna's reluctance to help only causes more problems. Can Hanna really tell Caleb what happened in the boat without tipping him off to her larger "A" problem? And if she did tell him, would he be willing to stick around after hearing all the horrible things Hanna has done? Meanwhile, Spencer follows a lead about "A" which guides her to an unexpected place and revelation.