Arima is the story of four women and a girl whose existence is disrupted by the sudden arrival of two strangers. One of them is fleeing from the other, sneaking around town like an elusive being, a ghostly presence of uncertain existence. The other character —an injured man carrying a gun— will disrupt the women's way of life in different ways. The whole plot takes place on the fine line between reality and imagination, between dreams and nightmares, fear and desire, within a story shrouded in mystery.

Galicia, northern Spain, January 2, 1921. The steamship Santa Isabel, sailing towards Argentina with more than two hundred emigrants on board, sinks off the coast of Sálvora Island. Three island women, María, Josefa and Cipriana, who have bravely set sail aboard a fragile skiff to save the shipwrecked, are treated as heroes by the cynical authorities; but León, an inquisitive and tenacious Argentinean journalist, starts asking uncomfortable questions.