Father Gregory (played by Jody Racicot) was a young priest who had left the Roman Catholic church and founded the Saint-Peter the Sinner's church in Alexandria, Virginia. He is characterized by his inverted crucifix, a symbol of the apostle Peter who asked to be crucified upside down, feeling unworthy to suffer the same death as his Lord Jesus Christ. Father Gregory was involved in the case of the half-angel quadruplet Nephilim who died as angels came to take their souls. Aware of the spiritual battle for their souls, Father Gregory tried to protect the girls, hiding one of them in his church, even though his actions made him appear guilty of their deaths. The inverted crucifix was initially mistaken by Mulder to mean Father Gregory's church was a Satanic cult. Father Gregory's efforts to adopt the girls were hindered by Satan disguised as a social worker named Aaron Starkey. Starkey threatened Father Gregory at the police station's interrogation room and killed him when he refused to cooperate.