Angels of Mercy tells the story of two Australian nursing sisters. One, the outback's first flying sister, single handedly battled the dust, heat and isolation of the Far West of NSW to bring medical treatment to her far flung patients, before the advent of the Flying Doctor. The other sister took up nursing with an eye to overseas travel, unaware that she would find herself in a battle zone and spend more than three years as a prisoner-of-war in Sumatra, as a 'guest' of the Emperor of Japan.