Sup with the devil and you'll taste your just desserts.

An evil Troll causes a Carnival poster to come to life - much to the bemusement of the passers-by. One such passer-by is a devout pastor, who is horrified at the decadent display erupting on the wall in front of him! He tries to intervene by way of an impromptu exorcism. But the exorcism backfires - with a vengeance! However the troll doesn't get away scot free! He gets his comeuppance, at the end of the movie, by way of a final, fearful warning...—Lee Gaskin