Madagascar. Joanna Lumley's spice journey continues on the African island of Madagascar. Travelling overland, she discovers the secrets of the world's second most expensive spice, vanilla. 3/4. Joanna Lumley sets off on one of her most epic voyages yet, a journey through the world's greatest spice continents to discover the rich tapestry of flavours and cultures which have shaped our world. Touring Indonesia, Zanzibar, India and Madagascar, Joanna explores the centuries-old spice trade.