Yves Klein was one of a kind. Noted as one of the most influential French artists of the post-war period, he moved beyond ideas of artistic representation. As part of his mission to 'make visible the absolute', he used blue as a vehicle, patenting his own bluer-than-blue hue – International Klein Blue (IKB) – in 1954. 70 years later, IKB endures, not only in this collection but as lasting legacy of Klein's quest for invisible truth.