Blood of My Blood

Federico, a young priest, is summoned by the 17th Century Inquisition to a convent prison in the town of Bobbio. His mission is to coerce Sister Benedetta to confess that she has seduced and driven to death her previous confessor, Federico's brother. Benedetta must undergo three trials - water, fire and tears - to prove her innocence if she does not confess. Federico, too, falls under the spell of the hypnotic Benedetta... The present-day Bobbio prison is run-down and abandoned. Tax investigator Federico is helping a Russian millionaire buy the old ruin. But a secretive old man has been living there for years. He is only occasionally seen out at night, and is referred to as "The Count". Federico needs to prove the man is a fraud to make the big sale...
(Source: The Match Factory - the-match-factory.com/catalogue/films/blood-of-my-blood.html)