Audrey remains in Haven to investigate her mother's connection to the Colorado Kid, but ends up working with Nathan to determine the cause of a mysterious series of incidents that involve butterflies and otherworldly phenomena centered on a angry reverend, his passive daughter, and her foster son.

A plague of insanity strikes at a local hospital, causing the doctors to go insane... and the patients to become normal. Audrey and Nathan seek to discover the cause before it spreads further.

A wedding at an isolated estate turns deadly for the guests when the site becomes sealed off and something attacks from within.