The Mercer family's fortune started in eighteenth-century England, increased via South African gems in the nineteenth, and is managed on an ethical basis today. But when a modern Mercer begins digging beneath the surface, the family's past suddenly appears less clear-cut than the gems they once traded. Set in the West Midlands of England in 1799 and 1999 and in Kimberley, South Africa in 1899, Luminosity tells three tales of interlinked lives where greed, lies and generosity have surprising results.

Luminosity premiered at The Pit, Barbican Centre, London, by the Royal Shakespeare Company in 2001.