Barcelona, 1932. Carmen Trillais a married woman, mother of twin girls and a boy who is suffering from tuberculosis. She lives in Barcelona with her husband, a renowned doctor with an excellent reputation in bourgeois society. Their relationship is deeply strained and constantly undermined by his infidelities, whose latest affair is with Carmen’s own sister. However, on a train journey from Barcelona to La Garriga, Carmen’s universe is turned upside down when she meets army captain Federico Escofet. It’s love at first sight and they embark upon a passionate, forbidden romance until they are discovered by Carmen’s husband, José María.
On 26 January, 1939, fascist troops enter Barcelona. Carmen finds herself forced to take the hardest decision of her life: she must escape, leaving her children in the care of her sister as she flees to France to try to save Federico, who is trapped in a concentration camp.
In spite of the distance, Carmen stays in contact with her daughters for years through letters that they exchange via their father. She is determined to return to Spain, but personal and political circumstances make that impossible.