Lila has learned from her father almost all there is to know about making fireworks. With the help of her friend Chulak, Lila discovers the final secret ... that anyone who wants to be a true firework-maker must face down the Fire-Fiend of Mount Merapi and bring back some of the royal sulphur. She has already set off on her quest when Chulak discovers the last bit of fatal information, so he must find her, before it's too late!