Filmmaker Tómas Gislason documented Eliasson's installation ‘Happiness’ at PinchukArtCentre, Kiev, in 2011. Viewers peer through a long horizontal opening in the gallery wall at eye height, into a world of constant change. Inside, a surface lit only by ultraviolet light is covered in clusters of drifting bubbles. More bubbles float through the dark space above, appearing bright and iridescent as they catch the light; they collide, merge, pop, or descend to rest on the liquid surface in a continual process of appearance, disappearance, and transformation.