This episode is about a woman, Amy who is haunted by dreams of an accident that she was involved in as a child that killed her mother. Amy makes the discovery that she can change things in her dream that also ultimately changes reality. Like going back in time.
The second half has Amy having psychic visions of a holocaust hitting Springwood, which turns out to be a prophecy. She has to get help from the military so they can stop the impending threat.