Katie and Kristi, the demon-plagued sisters from the films ‘Paranormal Activity’ and its part-sequel/part-prequel ‘Paranormal Activity 2,’ are back.

The trailer for the third installment in the hugely successful series reveals glimpses from the girls’ childhood and seems to provide context for why those nasty other-worldly beings were so hellbent on destruction in the first two flicks.

The moral of the story here seems to be, “Don’t poke sticks in supernatural cages.”

‘Paranormal Activity 3′ will premiere in October — just in time for Halloween.

[via Entertainment Weekly]