The Catholic rite distinguishes carefully between kinds of exorcism, and the distinctions are most of the theology. Minor exorcisms are ordinary and unremarkable: every baptism includes prayers renouncing evil, and blessed water and salt carry exorcistic formulas in the older books. The major or solemn exorcism is another matter, a reserved liturgy that only a priest appointed by the bishop may perform, and only upon a person, never merely a place, judged after serious investigation to be possessed.
The Rituale Romanum's famous rubrics, largely carried into the 1999 revision, are a checklist of scepticism: the exorcist must not readily believe possession is present, must distinguish it from illness and melancholy, and is directed to the classical signs, knowledge of hidden things, unlearned languages, strength beyond nature, together with vehement aversion to the sacred.
Modern norms add the modern sciences: psychiatric and medical evaluation is expected before the rite is considered, and exorcists' own associations describe the overwhelming majority of cases brought to them as needing doctors rather than the rite. When performed, the liturgy is sober: the Litany of the Saints, psalms, a Gospel, the laying on of hands, and the two formulas, deprecative, asking God to free the person, and imperative, commanding the spirit in the name of Christ to depart. The dramatic conventions of cinema, born of the 1973 film and its successors, sit far from the rite's actual texture, which is closer to a long, insistent prayer service than to spectacle.