Some pictures are now so mediated that their actual physicality has long been dwarfed by a million reproductions. The ‘Mona Lisa’, obviously. ‘The Haywain’ is the subject of countless cushion covers and trays. ‘The Birth of Venus’ has marketed trainers, hair dye and the New Yorker. Now, Georges Seurat’s ‘Un dimanche après-midi à l’Île de la Grande Jatte’, possibly the most famous painting to have inspired an entire musical and which has, along the way, inspired umbrellas, duvet covers, dresses, socks and face masks, is the subject of an ‘immersive’ creative experience.