Moulded from a single sheet of Plexiglas, Of One suggests infinite movement. Whereas Sullivan’s metallic sculptures manage to suggest weightlessness in spite of their actual weight, this goes one step further: it seems to dematerialize before the viewer’s eyes as light flows through it and its edges disappear. Its spiral shape punctuates Sullivan’s work throughout her career, from the spiralling movement of her body in the dances she choreographed to the accumulations of stones she created in the 1970s and the circular paintings of the 1980s.