An old war buddy catches up with Nolan at the same time a Castithan criminal with a history of violence enters the picture.

Rafe & Nolan search underground St. Louis while looking for an escaped convict. Meanwhile, a violent Castithan tradition causes clashes amongst the residents of Defiance.

Nolan and Irisa arrive in Defiance, where the town is soon divided over the death of Luke McCawley. But a bigger threat forces everyone together: An attack by the Volge.

A secret autopsy demonstrates the bizarre progression of the mystery virus, prompting Jim to make a startling confession. Eph and Nora race to find the father of the youngest victim…

The four survivors begin manifesting strange symptoms, but Eph and Nora’s attempt to quarantine them is thwarted as the disinformation campaign begins. Meanwhile, in jail, Setrakian receives a surprise visit…

When a plane lands in New York City with everyone on board dead, Dr. Ephraim Goodweather, head of the CDC’s Canary Project, and his team are called upon to investigate….