In a world of church closures, bankrupt dioceses and scandalized clergy, Sinner is the story of one Catholic priest's attempt to redeem his vocation and regain his integrity through an inconvenient muse. When his fundamentalist subordinate attacks Lil (Georgina Cates), a grifter who preys on celibates, Father Anthony Romano (Nick Chinlund) intervenes with the police and reluctantly provides her asylum in his rectory. Soon Father Anthony finds his private world invaded when Lil discovers a secret he has carefully hidden from his colleagues and parishioners.