The world of orchids is hotly competitive - but are the Midsomer orchid growers really killing each other?One of the world's rarest orchids is smuggled into Midsomer Malham from Borneo at a cost of hundreds of thousands of pounds, setting off a series of passionate events which lead to murder. Retired classics teacher Madeleine Villiers is poisoned with hemlock, then an orchid collector called Henry Plummer is found strangled. Brother Robert, a monk, obliges by translating Madeleine's diaries of her lurid sex life from the Latin. Barnaby has to find a plant of the Roth Orchid and at least one obsessive killer, while he is busy moving house.