What if colours could sing? What if you could not only see them, but hear them too? A Red that Sings transports the reader to the epicentre of Belgian modernism, where colour is more than just colour: it brings spectacle, vibrates and resonates. In the paintings of James Ensor, Rik Wouters and Jules Schmalzigaug, pigments are not silent elements but musical forces: vermilion cries out, blue clatters, yellow jangles and green blares. This book offers a compelling cultural history of colour as sound. Drawing on artists’ letters as well as art criticism, poetry, music and philosophy, it illustrates how modern artists and thinkers from Charles Baudelaire and Vincent van Gogh to Wassily Kandinsky, Alexander Scriabin and the Futurists sought synaesthetic connections between seeing and hearing. The ‘red that sings’ – a metaphor coined by Schmalzigaug – runs like a thread through a broader reflection on expression, emotion and modernity that takes in old acquaintances and modern masters, including Peter Paul Rubens and Henri De Braekeleer, as well as Adolphe Monticelli, Willem Paerels and Jean Brusselmans. This publication accompanies the exhibition A Red that Sings. Masterpieces by Ensor, Wouters and Schmalzigaug from 11 April 2026 to 30 August 2026 at the Royal Museum of Fine Arts Antwerp (KMSKA).