Gregory Motton's The World's Biggest Diamond takes place at a cottage by the sea. Two old lovers re-unite for a weekend after 30 years. He has an appointment with death, and she has left her husband upstairs. Both think the other has betrayed their love. They fight it out as a storm grows out at sea.

Gregory Motton's previous plays include Gengis Amongst the Pygmies (La Comedie Francaise, Paris), God's Island (Theatre de la Tempete, Paris), In Praise of Progress (Theatre de l'Odeon, Paris), A Monologue (Musee Dauphinois, Grenoble), A Little Satire (Gate), Cat and Mouse (Theatre de l'Odeon, Paris/Gate) and The Terrible Voice of Satan (Royal Court).