Sub is a 2006 French short film directed by Julien Loustau. The film delves into the enigmatic and potent nature of water, intertwining imagery of Chinese dams, cryobots, and the secluded Lake Vostok beneath Antarctica's ice. Through recurring visuals of dark, nocturnal currents, it evokes primal fears and curiosity, offering a poetic meditation on the mysteries hidden beneath the surface.