After the death of his parents, Hector is taken from the city to his grandfather Albert in a small coastal town in Brittany. Living with the grumpy and taciturn old man proves to be very difficult at first. However, Hector soon gains a loyal friend in Jean-Pière. After the two narrowly survive a sailing trip with the help of the grandfather, they stumble upon a dark secret that the old man has seemingly carried for a long time. They accidentally discover that April 12, 1944, must have played a key role in his life. Only after Albert's death do the two friends uncover the true events of the last year of the war...