The First Church of Eureka Is a small religious congregation in Eureka led by Reverend Harper. After Eureka is hit with his theory of religious-themed plagues caused by a temporal rift more of the citizens of Eureka door to join the congregation in search for answers. The sudden growth in the church's membership causes Sheriff Jack Carter to believe that Reverend Harper might have used her background as a theoretical physicist to cause the plagues. After the plagues are dealt with the church's congregation is still grown in size with more people opening up to the idea of believing in God.