The Castle of Otranto

A story of love and betrayal, the count Manfred seeks to marry his brother's widow Isabella who shows little interest in the new king. Manfred tries to persuade her to come out of the church she has taken refuge in when a mysterious army with strange interest in the marriage issue invades Manfred's realm. Who are these strange knights, and who is this Theodore that seeks to protect Isabella within the place she has taken sanctuary?