Demonic nun-fighting hero emerges from 'The Conjuring 2' mirror prank

As far as promotion stunts go, The Conjuring 2's approach in Australia is a pretty tried and tested formula. The old "scare the crap out of people with a two way mirror' prank. What they didn't bank on was an unlikely hero fighting back. 
The set up was simple. Have audience attend an exclusive warehouse screening of the movie, have them stick around after for a post-movie interview but leave them alone in a dressing room first so they can, you know, get beautiful for their close up.
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