In 1908 he moved to England to work for the Gaumont Film Company as a ‘cinematographic cameraman’. Soon afterwards he began work as a reporter for the London Daily Chronicle, travelling to report on events overseas. He learned to fly and take aerial photographs and, in 1912, he left England to report on the Balkan War, becoming the first person to take motion pictures in the front line of a war zone. In 1913 he accepted a place on a Canadian Arctic expedition and was still there in 1916 when he first heard that the world was at war.
On returning to Australia he was commissioned as a second lieutenant in the Australian Flying Corps but was prevented from operational flying because of colour blindness. In July 1917 he was appointed as an official photographer with the Australian Imperial Force (AIF) and reached the Western Front in time to photograph the Australians during the Passchendaele campaign. By mid 1918, now a captain, he was given command of No. 3 (Photographic) Sub-Section of the Australian War Records unit. More adventurer than photographer, Wilkins was sometimes a participant in, as well as an observer of, war. In June 1918 he was awarded the Military Cross for helping wounded under fire and, in September, earned a bar to the award for leading a group of inexperienced American soldiers through a dangerous action. He is the only Australian official photographer to have been decorated.
In January 1919 Wilkins travelled to the Gallipoli Peninsula as a photographer with the Australian Historical Mission under the official historian, Charles Bean. His appointment with the AIF ended on 7 September 1920.
In later life Wilkins set out to explore the Arctic by air and flew from Alaska to Norway, for which he was knighted. Wilkins won a number of awards for his pioneering exploration work. In November 1928 and January 1929 he explored the Antarctic by air, and in the 1930s, made five further expeditions to the Antarctic. In 1931 he unsuccessfully attempted to take a First World War submarine, the Nautilus, under the Arctic ice to the North Pole. He subsequently worked in defence-related positions with the US Weather Bureau and the Arctic Institute of North America.
Wilkins died on 30 November 1958 in Framingham, Massachusetts. He was so highly regarded in the United States that his ashes were scattered at the North Pole by the crew of an American nuclear submarine. His output is represented in the Australian War Memorial collection by eight films and hundreds of photographs from the First World War.