Plot

Life and events of the man who realized one of the most important discoveries of the 19th century: Altamira's caves.

Marcelino Sanz de Sautuola y de la Pedrueca, in 1868, accidentally discovered Paleolithic paintings with the help of a hunter named Modesto Cubillas inside Altamira's caves, located in Cantabria, northern Spain. Trying to expose their discovery to the academic world so that they could study the paintings, Sautuola incurred the scepticism and discredit of all experts, who claimed that the caves were false and the paintings made by Sautuola himself, in an effort to get rich. Looking for the truth, Sautuola spent the rest of his life fighting to prove that those paintings were real, trying to restore his innocence from the accusations of falsehood launched against him.—Chockys

In Paris, a man named Cartailhac speaks to a large group about the importance of scientific discoveries such as those of Charles Darwin. The movie goes back and forth between Cartailhac and the Monseñor telling his congregation the Church will not welcome anyone who tells people anything other than what is true about God and his creation.

At this point, adult Maria starts telling her story.

In 1878, Marcelino Sanz de Sautuola y de la Pedrueca and a man named Professor Vilanova attend the Exposition Universelle in Paris. There, one of the attractions is "primitives", a group of people who behave just as the cavemen did, in front of an audience. The two men have a conversation with Cartailhac. Then Marcelino returns home to Santander, Spain to his wife Conchita and his nine-year-old daughter Maria. He has presents, and Maria is so glad he is home. But she must practice the piano.

Later, Marcelino takes Maria to see a cave.

At an event at the Sautuola house, the entertainment includes an opera soprano. Then it is announced Maria will play the piano. Mero, a grouchy old man, who complains about everything, can't stand the idea of listening to a child and says so. Maria runs out.

The family goes to church and Maria won't confess to being angry if it means she must stop being angry. Conchita stops and compliments artist Paul on his work restoring a painting of Adam and Eve being tempted. Marcelino and Maria look at a rock that is being used to clean with.

Marcelino and Maria go to a cave that has not been opened for centuries and is now accessible. When Maria goes inside, she is amazed at the paintings of bison. Marcelino is also amazed. These paintings, he says, must be many thousands of years old, and yet they have not weathered and they look fresh.

When they return home, Conchita is annoyed Maria got dirty in a cave. Conchita and Marcelino have a conversation suggesting Conchita does not like for Maria to learn anything that contradicts what the Church says. How can anything be older than Adam and Eve? Conchita tells Maria she does not disapprove. Maria dreams the bison come to life.

After Vilanova examines the paintings, he talks to a group about the amazing discovery, saying they may be 10,000 years old and men from that time must have been as intelligent as men today. Mero says the paintings can't be that old. He says runaway slaves from Roman times did it. The Monseñor is there and concerned that Conchita is married to a man who believes such things, and he vows to make sure she understands what she should do.

As Conchita paints, Marcelino gets annoyed by comments in the newspaper by a writer who calls himself Tablanca and says Marcelino just wants fame.

The family visits the graves of two babies, both named Maria. It is stated later Conchita may still be angry over the loss of her two other children.

Maria is one of a group of children taught by a nun and Padre Tomás. They must all say together what is true about God and his creation. Maria makes the mistake of contradicting and is sent to a corner.

Conchita talks to Paul about his painting, which should look exactly as the artist intended. Paul is not so sure and thinks it may be impossible to know exactly how the painting appeared. Eve should smile because she is known to have experienced so much misery. Then Conchita talks to the Monseñor about her husband.

King Alfonso XII comes to see the cave. A big crowd gathers and photos are taken.

Paul visits the cave to make copies of the art. He is impressed. He says they could not be forgeries because forgers are looking to make money, and they do this by copying works that are well known and in demand.

Others visit the cave and believe the paintings are fake. Maria, who sneaked in, gets angry. Then she gets sick and sees visions that the bison stampede on her family's land and even invade the house.

Marcelino is determined to make a presentation in Lisbon to experts on archaeology. Conchita does not want him dealing with these atheists. When he does, Vilanova introduces him and calls the discoveries a miracle from God. Cartailhac ridicules the idea that there is such a thing as miracles and calls the Bible fairy tales. He also dismisses the discovery in the cave as a fairy tale. Why, for example, are there no soot marks? It is not possible to see without light, and light at that time caused soot. It has already been stated that there were no bison in the area because no bones were found, and that no other evidence can be found of such paintings that have been established to be as old as these. Marcelino protests that images of the bison have been found on rocks, and he shows one of those . Still, Cartailhac's comments damage Marcelino's reputation.

Paul's contribution is also called into question. Conchita's visits to Paul, it is suggested, may mean she is interested in him as she drifts apart from her husband.

If that isn't enough, Tablanca continues to disparage Marcelino, calling him unfit to be a father. Conchita recognizes comments she made to the Monseñor. She goes to confession and then confronts him. He defends himself by saying she was not confessing. She says she will not confess to him for fear of seeing hat she said to him later.

Maria gets upset again and runs out to a building on the property. She sees visions of everything covered in snow, and the bison on the property.

Pasi, the servant girl, shows Maria a type of oil that will not create soot marks. Marcelino hears this and tests the different types of oil. The oil Pasi used does not leave marks. At last, he can get his reputation back because one of the major objections is gone.

Marcelino takes Conchita to the cave and she is impressed.

Twenty years later Maria is an adult. Cartailhac visits to apologize to Marcelino personally. He is too late, as they have to visit his grave. But Cartailhac admits he was wrong, and the discoveries by Marcelino are now recognized as authentic.

The movie ends with the statements that similar evidence of ancient paintings was found in France, and the Santander paintings have been dated at 35,000 years old.