The film is based on the homonymous book by Francesc Escribano and adapted to the big screen by Albert Val and directed by Patrícia Font. El mestre que va prometre el mar delves into the life of Antoni Benaiges. He was a teacher from Mont-Roig del Camp in Baix Camp. In 1935, he was assigned to the public school in Bañuelos de Bureba, a small town in the province of Burgos. Thanks to a pioneering and revolutionary teaching methodology for the time, he begins to transform the lives of his students. He changes the people of the town. And that is not always to everyone's liking.

The protagonists are Enric Auquer and Laia Costa, Luisa Gavasa, Ramón Agirre, Milo Taboada, and the young debutants Nicolás Calvo, Alba Hermoso, and Gael Aparício, among others. The film is an Minoria Absoluta, Lastor Media, Filmax, and Mestres Films AIE production.