"call in a priest to perform an exorcism"

Exorcism is a practice existing in numerous world religions in which a religious leader commands an evil spirit to leave a place or person which it has supposedly possessed. Catholic Christian formal exorcisms are carried out by a priest and may involve a ritual, prayers and the invocation of Jesus Christ, God or certain angels to help evict the spirit. Anyone may say prayers of deliverance but formal exorcisms can be carried out if it is deemed necessary – it may take months until the spirit is thought to be gone.

Media attention in the latter half of the twentieth century saw a sharp rise in the number of exorcisms performed, helped along by the portrayal of exorcism in popular culture such as the 1973 horror film ‘The Exorcist’.