A European farm girl finds her younger sister unconscious in their barn. The sister's hand is bleeding and a mysterious book lies nearby. As she recovers, the girl's behavior becomes very strange, convincing her sister that the Devil is at work.

She goes to the exorcists Father Paul and Sister Maria for their help. They are both experienced in such matters and know that the only way to drive out the Devil is with pain. They drag the girl out of her room, strip her, and cuff her to a ceiling beam.
With dozens of merciless lashes of the whip, they try to expel the Devil from the helpless girl's naked body.

In the course of these proceedings, the older sister also becomes infested with the Devil when she's bitten by her sibling, and only the swift administration of similar measures will save her. So she´s bent over a table for a thorough ass-smacking with a wooden paddle.

Then her sister is brought to the table and whipped yet again until the Devil is finally cast out. The exorcism succeeds, but the price is high: the multitude of stripes on her body attest to the diligence of the two exorcists.