Irvine Green pencilled the title 'A Mouse at Moresby' on the cover of his war diary—a quiet nod to the 'Rats of Tobruk'. It was a fitting epithet for a man who, amid the chaos of war, used his camera and words to bear witness to the Pacific War in New Guinea. A Mouse of Moresby offers a firsthand account of World War II in New Guinea through the eyes of RAAF photographer Irvine Green. His rare photographs and personal diaries reveal the daily hardships of Australian servicemen facing Japan’s advance, capturing moments of courage, sacrifice, and endurance. As the Pacific War escalated, Irvine—a recent graduate of the RAAF photo survey course—was rushed to Port Moresby to assist with aerial reconnaissance and vital intelligence work. Armed with little more than his amateur skill and a resolve to serve, he became one of the few who documented, in real time, the critical period when New Guinea stood as Australia’s frontline. Stationed at HQ, Irvine had a unique perspective. His diaries and letters—written as events unfolded—offer a vivid, unfiltered account of the dread of invasion, the chaos of air raids, and the long, anxious wait for news. His lens and pen captured the tension, camaraderie, and day-to-day survival of those on the ground, as they joked to relieve stress and scavenged to get by. From the Fall of Rabaul and the Battle of the Coral Sea to the Kokoda Track, Irvine chronicled the conflict not from the vantage of generals or politicians, but from muddy airstrips, makeshift bunkers, and mess tents. His words and images reflect a frontline view of Australia’s fight for survival—raw, immediate, and deeply human. A Mouse of Moresby is not only a tribute to the resilience of Australian servicemen, but also an intimate portrait of a young man swept up in history. Featuring many previously unseen photographs, it offers a powerful glimpse into war, memory, and the lasting force of the image. Compiled by his son, Dr Tony Green, this book honours Irvine’s remarkable archive. Together, father and son bring to life the story Irvine never had the chance to publish—until now.