Coherence movie - Big Ideas in a Small Package

I have it on good authority that the 2013 indie movie Coherence is a smart, engaging work of sci fi.  The story concerns the strange events that unfold among a group of friends gathered for a dinner party after a comet is sighted.

It's got a big idea in a small package, with a feel reminiscent of the best of the original Twilight Zone TV series.  The film was shot largely at director/co-writer James Ward Byrkit's home; the main cast of eight worked with a loose script and improvised their dialogue.  If you recall, this was how The Blair Witch Project was done, and also the way the great Christopher Guest shoots his improv comedies like Best In Show and A Mighty Wind.

Here's the trailer of Coherence from You Tube: