Described by the author Monica Ali as a building that 'sparks the imagination and sparks conversations', 19 Princelet Street, now a Museum of Diversity and Immigration, captivated the imagination of teacher David Waters. He was struck by the building's potential not merely for exploring the diverse histories of migrant communities in London, but for showing pupils how those histories overlapped and intersected and were themselves intertwined with broader, national and international histories. This article describes how he used the building and its changing history as a locus for an exploration of the extent and nature of diversity in migrants' experiences. It demonstrates how a very localised depth study can act as a window into a much bigger world, both chronologically and thematically.