I think when I started to watch the episode, the sheriff of local law enforcement officer was my number one suspect and everything was going the way I thought - third case not connected, something else going on and I was already thinking - maybe the show has lost it's twist.. but hey.. I was making conclusions too early - this episode had a brilliant twist, brilliant writing and great score.. specially the piece playing in the end..
But with all that brilliant turn in the end.. I still felt the episode was maybe little bit unequal - the start was very raw and clear, nothing surprising, maybe slow.. and little off what we usually expect and then the turning point - when Emily gets.. the family is in it.. and that moment gave away the son. but.. then step by step we learn what really happen, they bring out the horror of so young boy.. how he did it.. and how he told it to Emily.. Really great reality break, great writing and I think the contrasts between the start and the end of the episode added even more.