In 1599 Italy, Beatrice Cenci is the teenage daughter of the crazed landowner and nobleman Francesco Cenci who keeps her locked up in the dungeon of his castle where he sexually abuses her. Beatrice plots with her stepmother, her besotted servant Olimpio, as well as a local bandit, named Catalano to plan Francesco’s murder.
When a journalist is murdered Inspector Micheli begins to investigate. Although someone comes forward to confess to the crime, Micheli doesn't believe he acted alone and keeps investigating despite coming under pressure to close the case.
