An American serving in WW1 falls in love with a very spirited nurse. On the Italy-Austrian front of World War I, Lt. Frederic Henry (Gary Cooper) is serving as an ambulance driver in the Italian army when he meets British nurse Catherine Barkley (Helen Hayes). He is a later wounded during an artillery barrage and is brought to a hospital in Milan where Barkley is assigned. They fall in love; their relationship is blessed post-facto by an Italian army chaplain. Henry returns to the front, but is frustrated that his correspondence with Barkley is blocked by his commanding officer Maj. Rinaldi (Adolphe Menjou) who is jealous of the relationship. Henry deserts and heads for Milan where he learns that Barkley, pregnant, has left for Switzerland. In Switzerland, Barkley is equally frustrated by the lack of correspondence from Henry. When her mail to Henry is returned to her, she collapses in shock, suffers a miscarriage, and becomes gravely ill. Henry finds her at the hospital and they profess their love as she dies in his arms. The movie closes with the ringing of church bells celebrating the signing of the Armistice and the end of the war