El Libro de piedra (The Book of Stone) is a 1969 Mexican supernatural horror film, written and directed by Carlos Enrique Taboada.

[1] Julia is hired to be the governess of a young girl, Sylvia who has an emotionally distant father, Eugenio, and a new stepmother, Mariana, since her mother passed away many years ago.

One night while at the dinner table, Julia sees a mysterious figure outside the window and Mariana ask Sylvia if it's her friend Hugo to which she angrily replies that it's not him so she is sent to her room for yelling.

On the way back Julia drops her necklace in the lake and is unable to get it but Sylvia tells her not to worry and assures her that Hugo will get it for her.

While going out with Carlos and Eugenio, Marina is driving and feels a strong pain in her wrist causing her to almost crash the car.

She also tells Julia that Hugo was the son of a black magic sorcerer who before dying learned of a way to revive after a thousand years but he had to make sure that his son would take care of the book until his revival so he made hugo hold the book and turned him into stone.

Marina then starts having a strong pain in her leg so Eugenio takes her to their room and call a doctor.

Mariana tells Eugenio that she feels threatened by something sinister and spiritual and that she can't stop thinking of Hugo.

The next day Erminia, the maid, finds Sylvia drawing a unicursal hexagram out of salt in the courtyard stating that she wants to bring her lizard (the same one that frightened Julia at the church) back to life.

The next day Erminia finds that lizard alive in her bedroom and tells Eugenio, Mariana, and Carlos about it.

The professor tells them that the symbol that is one that shouldn't be named but it could only be written with magical elements such as water, fire, salt, or blood.

That night Mariana hears a noise so goes to check it out and finds Sylvia out of bed and accuses her of trying to scare her and sends her to her room.

The next day police arrived at the house to give the news to Eugenio and asked him if he and another person could go identify the body.

Mariana then wakes up after hearing a noise and finds Sylvia is not in bed so she goes out looking for her by the lake but ends up running into Hugo's ghost instead.

After identifying Carlos' body, Eugenio and Julia return home and find all the house employees are awake standing outside.