‘Controlled Substances’ refers to those drugs which fall under government regulation. Hirst began this series of spot paintings in 1993 and a large selection were included in Jablonka Galerie’s ‘Damien Hirst’ solo exhibition (1993).

Each ‘Controlled Substance’ painting (‘Opium’) – often painted on irregularly shaped canvases – corresponds to a ‘Controlled Substance Key Painting’. The key assigns every colour used a letter and number in order to create an alphabet of spots, through which the drug title is concealed within the work.