Before Lisa Frank or the popularization of the Pride flag, there was a man known as the “rainbow artist.” Ay-Ō formerly took up with the experimental Fluxus movement, doing performance art involving breaking eggs on televisions and kicking around with Yoko Ono. He began exploring rainbow themes for built environments and installations, later moving on to silkscreen prints that capture these signature prismatic hues. Depicting sometimes banal or quiet scenes or abstract arrangements, the rainbow technique gives the effect of heat maps and adds a strange dimensionality to otherwise flat prints. In addition to the rainbow motif, Ay-Ō is known for his “finger boxes,” boxes with hidden compartments filled with various materials that visitors are invited to poke into, breaking all the usual taboos of museum-going. Several of these will be on hand to play with, and if being allowed to get your filthy paws on some art weren’t tantalizing enough, this exhibit comes with the rare but thrilling museum parental guidance warning, so expect some off-color subject matter along with those rainbows. Ay-Ō’s Happy Rainbow Hell runs from March 25 through Sept. 10 at the National Museum of Asian Art. Free.