Written and directed by James Ward Byrkit, Coherence follows a woman named Emily (played by Emily Baldoni) who must deal with strange occurrences following a comet sighting.
At the start of the film we are at a dinner party with eight people; during the dinner a comet passes over the house and causes the house to intertwine with multiple such houses and occupants from other realities. At first a power cut takes places which confuses the party guests then they notice across the street there is a house with lights on.
The party guests watch as two of the guys exit the house to go make a phone call from the “other house” and cross over into another reality. Their doubles come in from another reality. No one realises this switch.
As the story unfolds, they begin to realize that the other house is actually another version of theirs. But the group initially assumes that there are only two houses from two realities.
Later, they realise that there are multiple realities and that, once the comet passes, each reality will be stuck permanently with whoever stays in it.
There is a dark zone in between the realities. When people pass through the dark zone, they leave their reality and enter another reality at random.
The one person which the movie constantly follows is Emily…