The final season picks up two years after the brutal murder of Grace. The Stone family is in shambles as a devastated Ben continues to mourn his wife and search for his kidnapped daughter, Eden. Consumed by his grief, Ben has stepped down from his role as co-captain of the lifeboat, leaving Michaela to captain it alone, a near impossible feat with the passengers' every move now being monitored by a government registry. As the Death Date draws closer and the passengers grow desperate for a path to survival, a mysterious passenger arrives with a package for Cal that changes everything they know about Flight 828 and will prove to be the key to unlocking the secret of the Callings in this compelling, mind-bending, and deeply emotional journey.