This is the first scholarly monograph and most comprehensive documentation to date of the work of Yusuf Grillo (b. 1934) the influential Nigerian modernist painter, inaugural president of the Society of Nigerian Artists and founding director of School of Art, Design and Printing at the famous Yaba College of Technology, Lagos. Written by Chika Okeke-Agulu, the award-winning art historian and critic, and profusely illustrated in full colour, this book provides an unprecedented historical overview and critical examination of the Grillo's place within the history of 20th-century Nigerian art. Through persuasive reading of the artist's work, it argues that Grillo is incomparable among his peers in his vigorous, career-long engagement with the problem of colour and painting. For a member of the legendary Art Society, the group of young artists who at the dawn of political independence in the late 1950s and early 1960s, called for the decolonization of the art academy and establishment of national culture, Grillo's steadfast, painterly formalism is remarkable. His insistence on artistic sincerity, which for him meant locating painting's worth and significance in the relentless need to resolve the always-changing problems posed by colour, rather than in its ideological and cultural signification, exemplifies a pertinent vision and critical stance within the discourse and history of postcolonial modernism in Africa. Grillo's lifelong meditation on the blue palette is thus not so much an expression of his Yoruba cultural identity, as informed by his vision of painting as a longue-durée process and inquiry on specific problems of colour, its application, materiality, optics and affect. Colour for Grillo, the book argues, serves as a structuring device that allows him to make sense of and navigate the complex terrains of the phenomenal and metaphysical worlds. From the vantage of a single colour, Grillo imagines a painterly cosmos that is at once coherent and idiosyncratic, stable and dynamic; a world that can be instantaneously apprehended because it originates or revolves around a single colour system, yet impossible to comprehend because it stretches infinitely the possibilities of the monochromatic register. This explains why his exploration of the blue palette, without any vaunted, and indeed confining, ideological motivation or cultural imperative, continues to sustain his and our interest several decades on.