Demand for priests to perform exorcisms in Italy is on the rise, as an increasing number of Roman Catholics say they've been possessed by demons.

Nick Lazaredes explores the resurgence in popularity of the centuries-old ritual of exorcising the devil.

The Catholic church doesn't often allow the filming of exorcisms, but Nick is given a rare opportunity to watch as a woman who complained of nightmares and headaches goes through the intense and distressing experience.

But some dismiss it as a fraud and say it's just a marketing ploy to put the fear of God into people and get them back into church.

So are they suffering from demonic possession or just a delusion?

Interview with Nick - Nick talks about his story to SBS World News Australia Radio, including more on the arguments for and against exorcism.