Just when you think it can't get any crazier, it does. Nancy Grace investigates fringe group ideology.

Zombies, a cult, and the end of the world: Nancy Grace investigates 'cult mom' Lori Vallow.

Buried in the backyard: Nancy Grace investigates a grim discovery.

It's a tragic end to a twisted tale as the remains of 'cult mom' Lori Vallow’s children, JJ and Tylee, are found buried on their stepdad's property. Nancy Grace investigates the complex web of mysterious deaths, doomsday beliefs, and grim discoveries.

Doomsday, death and deception: Nancy investigates 'cult mom' Lori Vallow. Plus, inside sources reveal new bombshell information.