This essay focuses on a series of photographic negatives relating to the ground‐breaking exhibition Parallel of Life and Art, which opened at London's Institute of Contemporary Arts in 1953. Painstakingly preserved by one of the five exhibition‐makers, the artist‐photographer Nigel Henderson, these dark, translucent forms of photographic image offer the basis for a new interpretation of the exhibition. Crucially, they show how Parallel of Life and Art was rooted – technologically, aesthetically, and conceptually – in photographic negativity. This engagement with the negative found concentrated expression in four photographic images that Henderson created and integrated into the display. Simultaneously rejecting and reworking the conventions of modern art, these images enacted complex forms of negation, which inflected the exhibition as a whole. Read in dialogue with the negatives from Parallel of Life and Art, they pose profound challenges to the established distinctions between the artwork, the photograph, and the exhibition in post‐war Britain.