Twins Bul-Boo and Madillo think it an ominous coincidence when Fred - their best friend who lives next door - tells them that the ancient burial site mentioned by their eccentric teacher, Sister Leonisa, in a story featuring a disappearing child and a two-legged hyena, is the very same place to which his fearsome great-granny has determined to take him on a visit. In alternating first person narratives, the children describe their part in an unfolding mystery concerning people who have gone missing from the Aids clinic where the twins' mother works as a doctor. Set in modern-day Zambia, this adventure story for older readers (ideally Years 5 or 6) is very funny - and occasionally scary. But at the same time the novel touches on weightier themes, dramatising the competing claims of science and rational explanation with those of the world of spirits and ancient beliefs - both in the shape of the narrative and in its cast of memorable characters.