Las Vegas performer Deloris Van Cartier is surprised by a visit from her nun friends, Sister Mary Patrick, Sister Mary Lazarus and Mother Superior. Years ago they hid Deloris from her killer boyfriend, in their convent. While hiding in the convent Deloris helped to bring the community back to church by creating a singing group with the nuns. Now they return to find Deloris so that she can return the favor by helping with the troubled kids in their school. It appears Deloris is needed in her nun guise as Sister Mary Clarence to help teach music to teens in hopes of keeping the facility from closing. Can Deloris shape the rowdy kids into a real choir?