Injalak Hill in western Arnhem Land is known for its extraordinary wealth of rock art imagery spanning thousands of years. This corpus of rock art speaks to the changing nature of life and culture in this region - and to the skills of the many artists who added their marks over time. This includes artists working in the 'contact' period who continued to create rock art in the face of increasing incursions into their lands, disease, and frontier violence. Hidden within a secluded rock shelter on Injalak Hill, one particular rock painting tells a special story of culture contact. Nicknamed by Aboriginal Traditional Owners as the 'Buffaroo', it most probably represents an amalgamation of a traditional subject - the kunj or kangaroo - with a newly introduced animal - the nganaparru or water buffalo. In this paper, we argue that the Buffaroo represents a 'first-sight' painting - one that was produced before the artists became truly familiar with water buffaloes. This life-size painting most likely embodies a period of experimentation for Aboriginal artists before they had become fully acquainted with depicting this newly introduced animal in this region. Furthermore, this painting also hints at a process whereby nganaparru became integrated into artistic and cultural systems in northern Australia.