Tony Wendice maquina un plan para deshacerse de Margot, su esposa infiel. Pero la casualidad hará que sea a ella a quien finalmente acusen de asesinato. La inestimable ayuda de un inspector de policía ayudará a resolver el misterioso crimen.

A wealthy lord dies and is entombed with a valuable deposit of jewels. Seven keys are required to unlock the tomb and get hold of the treasure. A mad doctor uses an iron maiden to systematically eliminate the heirs to the fortune.

While her husband is away, Bluebeard's seventh wife sets out to discover all the secrets hidden in the castle using the keys he has given her. But she fails to see that by doing so she will be instrumental in creating a series of tragic events.

Separated a few months ago from Pedro, Matías invites Lucho to his house. But what seems to start fine will turn the tide when the past of Matías and Pedro’s relationship arrises in the form of the keys...

A powerful, emotional and sometimes humorous look at the daily life of a prison inmate and a corrections officer.