During the course of fieldwork at a Christian mission hospital in southern Zambia, I discovered that vernacular healers in the surrounding rural area were being visited by 'angel spirits' (bangelo) who offered them efficacious advice on how best to treat the patients under their care. According to the healers who encountered them, these angel spirits physically resembled white people (bakuwa), they dressed in white clothing, and their behaviour was inherently unpredictable. In this article, I consider what the presence of these angel spirits can tell us about moral attitudes towards humanitarian biomedicine in the region. But rather than focusing on these angel spirits alone, I situate them alongside a different non-human actor that has also been strongly identified with humanitarian biomedicine in southern Africa: the munyama or 'vampire'. By describing the behaviour of the human and non-human actors who have been historically associated with medical humanitarianism in southern Zambiavampires, angels, and European and American medical missionaries -I argue that it is possible to better understand why people in the region, from the mid-twentieth century to the present-day, have developed such a morally ambivalent attitude towards humanitarian biomedicine.