Hugh Hudson	...	(Director)
Olivia Hetreed, Olivia Hetreed	...	(Writer)
Clément Sibony	...	Émile Cartailhac
Rupert Everett	...	Monseñor
Javivi	...	Harlé (as Javivi Gil Valle)
Irene Escolar	...	María adulta
Nicholas Farrell	...	Vilanova
Allegra Allen	...	María Sautuola
Lluís Soler	...	Mero
Tábata Cerezo	...	Pasi
Golshifteh Farahani	...	Conchita
Chantal Garsan	...	Soprano
Concha Hidalgo	...	Marquesa
Katie Paterson	...	Carolina
Henry Goodman	...	De los Ríos
Maryam d'Abo	...	Elena
José Luis Esteban	...	Padre Tomás

Summary: 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, north to Spain. Trying to expose their discovery to the academic world for that they study the paintings, Sautuola crashed against the skepticism and discredit of all experts, who claimed that the caves were false and the paintings made for the own Sautuola, in a effort to get rich. Looking for the truth, Sautuola was 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.