With a mountain of seemingly damning evidence stacking up against him, Rex Heuermann's family struggles to understand how their beloved patriarch could be the monstrous serial killer law enforcement claims he is.

After Rex Heuermann is arrested and charged as the Gilgo Beach killer, a feverish hunt for information is undertaken -- but his family isn't talking; now, for the first time, the loved ones of the alleged killer speak publicly.

When searching for a missing woman, law enforcement on Long Island stumble upon the remains of other victims; as the killer of the so-called "Gilgo Four" remains elusive, police come to believe that the monster himself may live among them.