A jet-black train traverses the infinite and abstract landscape, its destination unknown. From a distance, its plume of smoke appears gentle—its steady chugging noises inviting. In closer proximity, however, the mechanism is a marvelous beast, its monstrous bellows sure to rattle any spectators to their core. It rapidly churns forward, forever thrashing. [Written by MAL Rewrite]

Pop consists of various monochrome images, including cel animation and drawings. The title is a reference to the sound of a passing train, as well as pop art. The animation won the second prize at the Zagreb Film Festival in Yugoslavia in 1974.