  In 1903, noted puzzle-maker Henry Dudeney published The Spider and the Fly
puzzle, which asks for the shortest path along the surfaces of a square prism
between two points (source and target) located on the square faces, and
surprisingly showed that the shortest path traverses five faces. Dudeney's
source and target points had very symmetrical locations; in this article, we
allow the source and target points to be anywhere in the interior of opposite
faces, but now require the square prism to be a cube. In this context, we find
that, depending on source and target locations, a shortest path can traverse
either three or four faces, and we investigate the conditions that lead to
four-face solutions and estimate the probability of getting a four-face
shortest path. We utilize a combination of numerical calculations, elementary
geometry, and transformations we call corner moves of cube unfolding diagrams,
