Catherine Dessin, a young French girl living in Paris during the occupation, falls for an older, married German officer. The novel examines the tensions this causes within her family of patriots and resistance workers. Meanwhile Klaus, the German officer, who is Oxford educated and a professed Anglophile, faces his own moral dilemma as he comes to realise, through his love for Catherine and a tragedy in his own family, the true nature of the regime he is serving.