Flatland tells the story of a square named A. Square, who lives in a two-dimensional world where all beings are geometric shapes. One day, A. Square encounters a sphere, a being from the third dimension. This revelation shakes the very foundation of Flatland society, as A. Square embarks on a journey to explore higher dimensions and challenge the strict social hierarchy of his world.

Set on the eve of Flatland's first mission into their 'outer-space,' the story presents the intriguing mysteries of triangles with angle sums greater than 180 degrees and flipping into dimensions that are literally out of this world.