This article explores how documentary film culture has supported the expansion of petromodernity in the 20th century. Often not explicitly concerned with advertising petroleum products, “oil films” or “petro-films” are an intriguing and sophisticated example of a public relations agenda that was bound up with cinema history and the pioneering individuals of international documentary movements. Focussing on the Shell Film Unit in Australia (SFUA), this article takes an ecocritical approach, synthesizing methods in film history and environmental history. The 1950s offers a rich and concise periodisation for the discussion—not only was it a crucial nation building moment in Australia, but also a pivotal juncture for recognition of “the environment”—at this time the conventional ecological meaning of this term was taking shape and gaining currency in the centres of the West as a measurable scientific and policy formation. In the 1950s the SFUA produced some of Australia’s most highly acclaimed documentaries, including The Back of Beyond (1954) and The Forerunner (1958) and invested in mobile film units to take cinema to the Australian outback. Shell’s films reached millions of viewers in Australia alone. This article argues that the SFUA’s practices and films recast the natural environment in ways that were specific to the Australian continent, and its topography, and thus facilitated an experience of modernity that was both founded on a relation with nature and bound up with the story of oil.