Spain, the year is 1944. The country is ruled by a fascist regime, led by General Franco. But there are many who do not want to put up with such power, and so throughout the country, groups of rebels lead a fierce resistance to the current regime. To perform the task of fighting one of these groups, operating in the mountainous part of northern Navarra, there with his entire family arrives capital Vidal. And then one day, while his father was busy fighting the guerrillas, his ten-year-old daughter Ophelia finds the entrance to a strange and mysterious labyrinth.